813 research outputs found

    Modelagem tridimensional do edifício Acaiaca: avaliação bioclimática de uma obra modernista brasileira

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    CIES2020 - XVII Congresso Ibérico e XIII Congresso Ibero-americano de Energia SolarRESUMO: Delfim Amorim, arquiteto modernista do edifício Acaica, utilizou arranjos bioclimáticos construtivos (peitoril ventilado, generosas aberturas, brises verticais fixos e cobogós), a fim de otimizar o aproveitamento dos recursos naturais (ventilação natural e iluminação natural) dentro do edifício e promover o conforto ambiental aos usuários. O objetivo do artigo é através da modelagem tridimensional do edifício Acaiaca (utilizando o software Blender), avaliar os arranjos construtivos, que possam promover a qualidade bioclimática do edifício. Para o desenvolvimento da pesquisa foi realizado o percurso metodológico: Coleta documental e pesquisa bibliográfica do Acaiaca; Visita ao edifício; Aprofundamento teórico sobre qualidade ambiental e arquitetura bioclimática; Análise da qualidade ambiental do Acaiaca. Constatou-se que o edifício possui uma série de dispositivos bioclimários, o que contribuiria no controle do desperdício de energia e na qualidade ambiental do edifício, no entanto alguns moradores interviram nesses arranjos obstruindo as aberturas (peitoril ventilado e brises verticais), modificando o desempenho do edifício.ABSTRACT: Delfim Amorim, modernist architect of the Acaica building, used constructive bioclimatic arrangements (ventilated sill, generous openings, fixed vertical windshields and cobogós), in order to optimize the use of natural resources (natural ventilation and natural lighting) within the building and promote comfort to users. The objective of the article is through the three-dimensional modeling of the Acaiaca building (using the Blender software), to evaluate the construction arrangements, which can promote the building's bioclimatic quality. For the development of the research, the methodological path was carried out: Documentary collection and bibliographic research of Acaiaca; Visit to the building; Theoretical deepening on environmental quality and bioclimatic architecture; Analysis of the environmental quality of Acaiaca. It was found that the building has a series of bioclimatic devices, which would contribute to the control of energy waste and the environmental quality of the building, however some residents intervened in these arrangements by blocking the openings (ventilated sill and vertical breezes), modifying the performance of the building.info:eu-repo/semantics/publishedVersio

    Square to stripe transition and superlattice patterns in vertically oscillated granular layers

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    We investigated the physical mechanism for the pattern transition from square lattice to stripes, which appears in vertically oscillating granular layers. We present a continuum model to show that the transition depends on the competition between inertial force and local saturation of transport. By introducing multiple free-flight times, this model further enables us to analyze the formation of superlattices as well as hexagonal lattice

    Front Propagation of Spatio-temporal Chaos

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    We study the dynamics of the front separating a spatio-temporally chaotic region from a stable steady region using a simple model applicable to periodically forced systems. In particular, we investigate both the coarsening of the front induced by the inherent `noise' of the chaotic region, and the long wavelength dynamics causing the front to develop cusps

    Nanoparticles In Treatment Of Thermal Injured Rats: Is It Safe?

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    The aim of this study was to assess whether thermal trauma induced oxidative stress altered the balance between oxidant and antioxidant systems in the blood of burn wound rats in the absence and presence of silver nanoparticles and S-nitrosoglutathione, GSNO. Free silver nanoparticles, free GSNO and silver nanoparticles + GSNO had no cytotoxic effects. Under anesthesia, the shaved dorsum of the rats was exposed to 90°C (burn group) water bath. Studied compounds were administered topically immediately and at 28 days after the burn injury, four times a day. Silver nanoparticles and silver nanoparticles + GSNO were no toxic in vitro and in vivo. There were no significant differences in the levels of urea, creatinine, aminotransferases and hematological parameters, in control-burn groups (free silver nanoparticles) and treated-burn groups (free GSNO or silver nanoparticles + GSNO). There were no differences in lipid peroxidation and in the levels of protein carbonyls and glutathione, used as oxidative stress markers. A little inflammatory cell response, papillary dermis vascularization, fibroblasts differentiated into contractile myofibroblasts and the presence of a large amount of extracellular matrix were evidenced in treated groups following skin injury. These results indicate that silver nanoparticles and GSNO may provide an effective action on wound healing.3041Tian, J., Wong, K.K.Y., Ho, C.M., Lok, C.N., Yu, W.Y., Che, C.M., Chiu, J.F., Tam, P.K.H., (2007) J. Chem. Med. Chem., 2, p. 129Teli, M.K., Mutalik, S., Rajanikant, G.K., (2010) Cur. Pharm. Design., 16, p. 1882Schaller, M., Laude, J., Bodewaldt, H., Hamm, G., Korting, H.C., (2004) Skin Pharmacol. Physiol., 17, p. 31Seabra, A.B., Da Silva, R., De Souza, G.F.P., De Oliveira, M.G., (2008) Artif. Organs, 32, p. 262Seabra, A.B., Pankotai, E., Fehér, M., Somlai, A., Kiss, L., Bíró, L., Szabó, C., Lacza, Z., (2007) Br. J. Dermatol., 156, p. 814Seabra, A.B., Martins, D., Simes, M.M.S.G., Da Silva, R., Brocchi, M., De Oliveira, M.G., (2010) Artif. Organs, 34, p. 204Durán, N., Marcato, P.D., Alves, O.L., De Souza, G.I.H., Esposito, E., (2005) J. Nanobiotechnol., 3, p. 1Durán, N., Marcato, P.D., De Souza, G.I.H., Alves, O.L., Esposito, E., (2007) J. Biomed. Nanotechnol., 3, p. 203Amadeu, T.P., Seabra, A.B., De Oliveira, M.G., Costa, A.M.A., (2007) J. Eur. Acad. Dermatol. Venereol., 21, p. 629Amadeu, T.P., Seabra, A.B., De Oliveira, M.G., Costa, A.M.A., (2008) J. Surg Res., 149, p. 84Correa, D.H.A., Melo, P.S., De Carvalho, C.A.A., De Azevedo, M.B.M., Durán, N., Haun, M., (2005) Eur. J. Pharmacol., 510, p. 17De Conti, R., Oliveira, D.A., Fernandes, A.M.A.P., Melo, P.S., Rodriguez, J.A., Haun, M., Castro, S.L., Durán, N., (1998) Vitro Mol. Toxicol, 11, p. 153Borefreund, E., Puerner, J.A., (1984) J. Tissue Cult. Methods, 9, p. 7Denizot, F., Lang, R., (1986) J. Immunol. Methods, 89, p. 271Michailidis, Y., Jamurta, A.Z., Nikolaidis, M.G., Fatouros, I.G., Koutedakis, Y., Papassotiriou, I., (2007) Med. Sci. Sport Exerc., 39, p. 1107Davis, T.A., Amare, M., Naik, S., Kovalchuk, A.L., Tadaki, D., (2007) Wound Repair Regen., 15, p. 57

    Percolation model for structural phase transitions in Li1x_{1-x}Hx_xIO3_3 mixed crystals

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    A percolation model is proposed to explain the structural phase transitions found in Li1x_{1-x}Hx_xIO3_3 mixed crystals as a function of the concentration parameter xx. The percolation thresholds are obtained from Monte Carlo simulations on the specific lattices occupied by lithium atoms and hydrogen bonds. The theoretical results strongly suggest that percolating lithium vacancies and hydrogen bonds are indeed responsible for the solid solution observed in the experimental range 0.22<x<0.360.22 < x < 0.36.Comment: 4 pages, 2 figure

    Novel coumarins active against Trypanosoma cruzi and toxicity assessment using the animal model Caenorhabditis elegans

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    From 2nd Latin American Congress of Clinical and Laboratorial Toxicology Porto Alegre, Brazil. 3-6 June 2018Background: Chagas disease (CD) is a tropical parasitic disease. Although the number of people infected is very high, the only drugs available to treat CD, nifurtimox (Nfx) and benznidazole, are highly toxic, particularly in the chronic stage of the disease. Coumarins are a large class of compounds that display a wide range of interesting biological properties, such as antiparasitic. Hence, the aim of this work is to find a good antitrypanosomal drug with less toxicity. The use of simple organism models has become increasingly attractive for planning and simplifying efficient drug discovery. Within these models, Caenorhabditis elegans has emerged as a convenient and versatile tool with significant advantages for the toxicological potential identification for new compounds. Methods: Trypanocidal activity: Forty-two 4-methylamino-coumarins were assayed against the epimastigote form of Trypanosoma cruzi (Tulahuen 2 strain) by inhibitory concentration 50% (IC50). Toxicity assays: Lethal dose 50% (LD50) and Body Area were determined by Caenorhabditis elegans N2 strain (wild type) after acute exposure. Structure-activity relationship: A classificatory model was built using 3D descriptors. Results: Two of these coumarins demonstrated near equipotency to Nifurtimox (IC50 = 5.0 ± 1 μM), with values of: 11 h (LaSOM 266), (IC50 = 6.4 ± 1 μM) and 11 g (LaSOM 231), (IC50 = 8.2 ± 2.3 μM). In C. elegans it was possible to observe that Nfx showed greater toxicity in both the LD50 assay and the evaluation of the development of worms. It is possible to observe that the efficacy between Nfx and the synthesized compounds (11 h and 11 g) are similar. On the other hand, the toxicity of Nfx is approximately three times higher than that of the compounds. Results from the QSAR-3D study indicate that the volume and hydrophobicity of the substituents have a significant impact on the trypanocidal activities for derivatives that cause more than 50% of inhibition. These results show that the C. elegans model is efficient for screening potentially toxic compounds. Conclusion: Two coumarins (11 h and 11 g) showed activity against T. cruzi epimastigote similar to Nifurtimox, however with lower toxicity in both LD50 and development of C. elegans assays. These two compounds may be a feasible starting point for the development of new trypanocidal drugs
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