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61.
Milan Batista 《Engineering Structures》2011,33(1):265-272
Two theories of shear deformable plate vibrations that account for the influence of the transverse normal stress component are derived. The first is a slightly modified Mindlin theory, including a shear correction factor, while in the second the use of the shear correction factor is replaced by stress components that exactly satisfy elasticity motion equations and plate face boundary conditions. A comparison with the exact 3D solution for a sinusoidally loaded rectangular plate and infinite strip is made. It is found that the refined theories significantly increase the accuracy of results compared to the original Mindlin theory. 相似文献
62.
Natlia Lins da Silva-Gomes Leonardo Alexandre de Souza Ruivo Claudia Moreira Marcelo Meuser-Batista Cristiane Frana da Silva Denise da Gama Jaen Batista Stênio Fragoso Gabriel Melo de Oliveira Maria de Nazar Correia Soeiro Otacilio C. Moreira 《International journal of molecular sciences》2022,23(23)
Ecto-nucleoside triphosphate diphosphohydrolases (NTPDases) are enzymes located on the surface of the T. cruzi plasma membrane, which hydrolyze a wide range of tri-/-diphosphate nucleosides. In this work, we used previously developed genetically modified strains of Trypanosoma cruzi (T. cruzi), hemi-knockout (KO +/−) and overexpressing (OE) the TcNTPDase-1 gene to evaluate the parasite infectivity profile in a mouse model of acute infection (n = 6 mice per group). Our results showed significantly higher parasitemia and mortality, and lower weight in animals infected with parasites OE TcNTPDase-1, as compared to the infection with the wild type (WT) parasites. On the other hand, animals infected with (KO +/−) parasites showed no mortality during the 30-day trial and mouse weight was more similar to the non-infected (NI) animals. In addition, they had low parasitemia (45.7 times lower) when compared with parasites overexpressing TcNTPDase-1 from the hemi-knockout (OE KO +/−) group. The hearts of animals infected with the OE KO +/− and OE parasites showed significantly larger regions of cardiac inflammation than those infected with the WT parasites (p < 0.001). Only animals infected with KO +/− did not show individual electrocardiographic changes during the period of experimentation. Together, our results expand the knowledge on the role of NTPDases in T. cruzi infectivity, reenforcing the potential of this enzyme as a chemotherapy target to treat Chagas disease (CD). 相似文献
63.
Fabiana Furci Giuseppe Murdaca Alessandro Allegra Luca Gammeri Gianenrico Senna Sebastiano Gangemi 《International journal of molecular sciences》2022,23(23)
Coronavirus SARS-CoV-2 has represented, and still represents, a real challenge from a clinical, diagnostic and therapeutic point of view. During acute infection, the increased levels of pro-inflammatory cytokines, which are involved in the pathology of disease and the development of SARS-CoV-2-induced acute respiratory disease syndrome, the life-threatening form of this infection, are correlated with patient survival and disease severity. IL-33, a key cytokine involved in both innate and adaptive immune responses in mucosal organs, can increase airway inflammation, mucus secretion and Th2 cytokine synthesis in the lungs, following respiratory infections. Similar to cases of exposure to known respiratory virus infections, exposure to SARS-CoV-2 induces the expression of IL-33, correlating with T-cell activation and lung disease severity. In this work, we analyse current evidence regarding the immunological role of IL-33 in patients affected by COVID-19, to evaluate not only the clinical impact correlated to its production but also to identify possible future immunological therapies that can block the most expressed inflammatory molecules, preventing worsening of the disease and saving patient lives. 相似文献
64.
65.
Lopez Daniel Andres Sanchez Chagas Luciana Gomes Batista Aline Domingues Guaita Maria Gabriella Detone Amorin Luís Henrique Cardozo da Silva Paulo Rogério Catarini Yamanishi Gustavo Zaia Dimas Augusto Morozin de Santana Henrique Urbano Alexandre 《Journal of Materials Science: Materials in Electronics》2021,32(13):17462-17472
Journal of Materials Science: Materials in Electronics - The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the... 相似文献
66.
Pedro Martins Rui Caseiro Jorge Batista 《Computer Vision and Image Understanding》2013,117(3):250-268
This work addresses the matching of a 3D deformable face model to 2D images through a 2.5D Active Appearance Models (AAM). We propose a 2.5D AAM that combines a 3D metric Point Distribution Model (PDM) and a 2D appearance model whose control points are defined by a full perspective projection of the PDM. The advantage is that, assuming a calibrated camera, 3D metric shapes can be retrieved from single view images. Two model fitting algorithms and their computational efficient approximations are proposed: the Simultaneous Forwards Additive (SFA) and the Normalization Forwards Additive (NFA), both based on the Lucas–Kanade framework. The SFA algorithm searches for shape and appearance parameters simultaneously whereas the NFA projects out the appearance from the error image and searches only for the shape parameters. SFA is therefore more accurate. Robust solutions for the SFA and NFA are also proposed in order to take into account the self-occlusion or partial occlusion of the face. Several performance evaluations for the SFA, NFA and theirs efficient approximations were performed. The experiments include evaluating the frequency of converge, the fitting performance in unseen data and the tracking performance in the FGNET Talking Face sequence. All results show that the 2.5D AAM can outperform both the 2D + 3D combined models and the 2D standard methods. The robust extensions to occlusion were tested on a synthetic sequence showing that the model can deal efficiently with large head rotation. 相似文献
67.
Valéria da Penha Freitas Jairo Pinto de Oliveira Marco Cesar Cunegundes Guimarães Fabiana Mantovani Gomes França Cecília Pedroso Turssi Roberta Tarkany Basting 《Journal of Adhesion Science and Technology》2018,32(16):1822-1837
This study evaluated the effect of different cementing strategies and adhesive interface aging on microtensile bond strength (μTBS) of lithium disilicate ceramic (IPS e.max CAD) to dentin. Forty coronal dentin fragments were randomly assigned to four groups according to the cementing strategy used to bond lithium disilicate ceramic to coronal dentin surface (n = 10): U200 (self-adhesive resin cement (RC) RelyX U200®/3 M ESPE), SBU (single-step self-etching adhesive system (AS) Single Bond Universal®/3 M ESPE + RelyX ARC®/3 M ESPE RC), AdperSB (two-step etch-and-rinse AS Single Bond 2®/3 M + RelyX ARC®/3 M ESPE RC) and Scotchbond (three-step etch-and-rinse AS Scotchbond Multi-Purpose®/3 M + RelyX ARC®/3 M RC). After 48 h, the ceramic-tooth blocks were sectioned perpendicular to the adhesive interface in the form of sticks and randomly subdivided into two groups according to when they were to be submitted to μTBS testing: immediately or 6 months after storage in water. Some sticks were kept for analysis of the adhesive interface by scanning electron microscopy (SEM). The μTBS test was performed in a universal testing machine (0.5 mm/min). The data (MPa) were analyzed using split-plot ANOVA and Tukey’s test (α = 0.05). Water storage decreased μTBS in all cementing strategies. The μTBS was greatest in the Scotchbond group and lowest in the U200 group, at both storage times. No signs of interface degradation were detected under SEM after water storage. In conclusion, water storage decreased bond strength, regardless of the adhesive cementation strategy, and that the three-step adhesive system/dual-cure resin cement ultimately performed better in terms of bond strength. 相似文献
68.
Daniela Domanski Guillermina Urretavizcaya Facundo J. Castro Fabiana C. Gennari 《Journal of the American Ceramic Society》2004,87(11):2020-2024
MgAl2 O4 spinel was successfully synthesized using a mechanochemical route that avoided the formation and calcination of its precursors at high temperatures. The method involved a single step in which γ-Al2 O3 –MgO, AlO(OH)–MgO, and α-Al2 O3 –MgO mixtures were milled at room temperature under air atmosphere. The formation of MgAl2 O4 occurred faster with γ-Al2 O3 than with AlO(OH) or α-Al2 O3 . After 140 h, the mechanochemical treatment of the γ-Al2 O3 –MgO mixture yielded 99% of MgAl2 O4 . 相似文献
69.
Thais Vasconcelos Batista Milano Gadelha Carvalho 《Electronic Notes in Theoretical Computer Science》2002,65(4)
This paper presents a mechanism for dynamic reconfiguration of component-based applications and its fault tolerance strategy. The mechanism, named generic connector, allows composing a component-based application as a set of services with no previous knowledge about the specific components that will provide some services. The components will be selected at runtime. The objective of this work is to offer a mechanism that tries to satisfy every invocation under its responsibility and makes failures as transparent as possible. It is an important tool to compose applications through the reuse of existing components because it frees the programmer from the task of searching components in order to use them and, also, from solving some types of failures. 相似文献
70.
Barreto L.H.S.C. Coelho E.A.A. Farias V.J. de Oliveira J.C. de Freitas L.C. Joao Batista Vieira Jr. 《Industrial Electronics, IEEE Transactions on》2005,52(2):552-557
This paper presents a quadratic boost converter using a single quasi-resonant network to reach soft commutation. A resonant inductor, a resonant capacitor, and an auxiliary switch form the resonant network and the main switch operates in a zero-current-switching way. A complete analysis of this converter is presented. According to the simulation and experimental results, this quadratic boost converter provides a larger conversion ratio than that provided by the conventional boost converter (for a given duty ratio D), and presents optimum performance, which operates with soft-switch commutation using a single resonant network. 相似文献