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51.
Ana C. Afonso Diana Oliveira Maria Jos Saavedra Anabela Borges Manuel Simes 《International journal of molecular sciences》2021,22(15)
Diabetic foot ulcers (DFUs) are a serious complication from diabetes mellitus, with a huge economic, social and psychological impact on the patients’ life. One of the main reasons why DFUs are so difficult to heal is related to the presence of biofilms. Biofilms promote wound inflammation and a remarkable lack of response to host defences/treatment options, which can lead to disease progression and chronicity. In fact, appropriate treatment for the elimination of these microbial communities can prevent the disease evolution and, in some cases, even avoid more serious outcomes, such as amputation or death. However, the detection of biofilm-associated DFUs is difficult due to the lack of methods for diagnostics in clinical settings. In this review, the current knowledge on the involvement of biofilms in DFUs is discussed, as well as how the surrounding environment influences biofilm formation and regulation, along with its clinical implications. A special focus is also given to biofilm-associated DFU diagnosis and therapeutic strategies. An overview on promising alternative therapeutics is provided and an algorithm considering biofilm detection and treatment is proposed. 相似文献
52.
Diogo Mendes David Sousa Ana C. Cerdeira Laura C.J. Pereira Ana Marques João Murta-Pina Anabela Pronto Isabel Ferreira 《Ceramics International》2021,47(1):381-387
High-performance YBCO 123 (YBa2Cu3O7-x) bulk superconductor samples were produced using the 3D printing paste-extrusion technique. The YBCO powder obtained after sintering a pre-mixture of Y2O3, BaCO3 and CuO powders at 950 °C was used in the formulation of pastes for extrusion in a 3D freeform printer. The 3D samples printed from pastes containing the pre-mixture powders were sintered, while those produced using the YBCO powder were not. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and Raman analysis all confirmed the YBCO phase after sintering, both in the powder and in the samples made with the pre-mixture. Scanning electron microscopy (SEM) images revealed powder grains of heterogeneous size and geometry, as well as grain aggregation, in the sintered samples. Superconducting quantum interference device (SQUID) measurements taken within a fixed magnetic range revealed that the printed pieces have a typical magnetization temperature of 92 K, reaching ?1.43 emu/g and ?1.59 emu/g respectively a zero-field-cooled magnetization (ZFC) for sintered and non-sintered printed samples. 相似文献
53.
54.
55.
Linhares Claudio D. G. Ponciano Jean R. Pereira Fabíola S. F. Rocha Luis E. C. Paiva Jose Gustavo S. Travençolo Bruno A. N. 《Multimedia Tools and Applications》2020,79(25-26):17645-17667
Multimedia Tools and Applications - Networks are often used to model the structure of interactions between parts of a system. One important characteristic of a network is the so-called network... 相似文献
56.
Marcelo de Paiva Guimarães Diego Roberto Colombo Dias José Hamilton Mota Bruno Barberi Gnecco Vinícius Humberto Serapilha Durelli Luis Carlos Trevelin 《Multimedia Tools and Applications》2018,77(1):347-361
This study explores the possibility of effectively using web-standard technologies (i.e., HTML5, JavaScript, WebGL, and WebRTC) to deploy full immersive and interactive virtual reality applications. These applications are based on computer clusters and run in multi-projection environments, such as CAVEs, Panoramas and Power Walls. Until recently, these applications were build using tailored solutions, such low-level libraries to distribute data. We discuss the modern-day web technology which allows these applications meet a multi-platform requirement. This paper also evaluates the communication and synchronization requirements of these applications that are traditionally the main bottleneck. As a proof-of-concept to show the feasibility of our study, we devised and implemented an immersive and interactive virtual reality application employing only web technologies. Our proof-of-concept runs on a miniCAVE environment with three displays and a 6-node cluster. 相似文献
57.
Marta Abrantes Maria Salete Balula Anabela A. Valente Filipe A. Almeida Paz Martyn Pillinger Carlos C. Romão João Rocha Isabel S. Gonçalves 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(1):215-222
The organotin vanadate [Me3SnVO3] (1) has been prepared and characterised in the solid state by powder X-ray diffraction (XRD), thermogravimetric analysis, multinuclear
magic-angle spinning (MAS) NMR, IR and Raman spectroscopy. The phase purity and structure of microcrystalline 1 were confirmed by carrying out a full Rietveld structural refinement at ambient temperature and from conventional powder
XRD. 51V and 119Sn MAS NMR data for compound 1 were in agreement with the predicted structure, showing two equally-abundant, nonequivalent Me3Sn groups and two equally-abundant, nonequivalent vanadium atoms. The compound was applied as a catalyst for the liquid-phase
epoxidation of olefins at 55 °C using tert-butyl hydroperoxide (tBuOOH) as the oxidant. The reaction rate for the different substrates followed the order cis-cyclooctene > (R)-(+)-limonene ≅ trans-2-octene > cyclododecene > styrene > 1-octene; the corresponding epoxides were the
only observed products. Leaching tests indicated that the catalytic epoxidation of cyclooctene was mainly heterogeneous in
nature.
This paper is dedicated to Professor Ian Manners and his scientific accomplishments. 相似文献
58.
Ocar Aurelio Mendoza Reales William C. PearlJr. Maria D. M. Paiva Cristiane R. Miranda Romildo Dias Toledo Filho 《Frontiers of Structural and Civil Engineering》2016,10(2):174-179
This work studies the influence of a commercial dispersion of multi wall carbon nanotubes (MWCNT) on the hydration of a class G cement paste, at room and elevated down-hole temperatures. The MWCNT dispersion was produced with a solids concentration of 3.0 % by mass and an anionic surfactant as dispersing agent. Cement pastes with water-to-cement ratio of 0.45 and additions of solid MWCNT by mass of cement up to 0.50 % were studied. Isothermal calorimetry results showed a clear retardation of the hydration of cement caused by the surfactant contained in the MWCNT dispersion. Nevertheless, thermogravimetric evaluations showed that once the hydration reaction resumed, the retardation effect of the surfactant did not have a negative impact on the amount of hydration products precipitated. It was concluded that the commercial MWCNT dispersion presents a good potential to be applied in oil well cement pastes. 相似文献
59.
A variable elimination method to improve the parsimony of MLR models using the successive projections algorithm 总被引:5,自引:0,他引:5
Roberto Kawakami Harrop Galvo Mrio Csar Ugulino Araújo Wallace Duarte Fragoso Edvan Cirino Silva Gledson Emidio Jos Sfacles Figueredo Carreiro Soares Henrique Mohallem Paiva 《Chemometrics and Intelligent Laboratory Systems》2008,92(1):83-91
The successive projections algorithm (SPA) is a variable selection technique designed to minimize collinearity problems in multiple linear regression (MLR). This paper proposes a modification to the basic SPA formulation aimed at further improving the parsimony of the resulting MLR model. For this purpose, an elimination procedure is incorporated to the algorithm in order to remove variables that do not effectively contribute towards the prediction ability of the model as indicated by an F-test. The utility of the proposed modification is illustrated in a simulation study, as well as in two application examples involving the analysis of diesel and corn samples by near-infrared (NIR) spectroscopy. The results demonstrate that the number of variables selected by SPA can be reduced without significantly compromising prediction performance. In addition, SPA is favourably compared with classic Stepwise Regression and full-spectrum PLS. A graphical user interface for SPA is available at www.ele.ita.br/kawakami/spa/. 相似文献
60.
F. M. M. Pereira C. A. R. Junior M. R. P. Santos R. S. T. M. Sohn F. N. A. Freire J. M. Sasaki J. A. C. de Paiva A. S. B. Sombra 《Journal of Materials Science: Materials in Electronics》2008,19(7):627-638
The M-type barium hexaferrite Ba
x
Sr1−x
Fe12O19 (where 0 < x < 1) alloys were prepared by a new ceramic procedure. The samples were studied using X-ray diffraction and Rietveld analysis,
scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, infrared and M?ssbauer spectroscopy. The X-ray analysis
indicates that the all the samples present a hexagonal structure. The IR spectra showed three main absorption bands in range
of 400–600 cm−1 corresponding to SFO100 and BFO100. The M?ssbauer spectra showed a superposition of five subspectra associated with the five
sites of the iron ion, which in the ferric state. The SEM studies showed that the hexaferrites presented grains that varied
in the range of 260–305 nm. The dielectric properties: dielectric constant (ε′) and dielectric loss (tg δ) were measured at room temperature in the frequency range from 100 Hz to 40 MHz. The samples present a nonlinear behavior
for the dielectric constant at 100 Hz, 1 kHz and 1 MHz. The dielectric constant is not following the linear mixing rule for
the samples. The structural, dielectric and magnetic properties of the composite barium hexaferrite phases were discussed
in view of applications as a material for permanent magnets, high density magnetic recording and microwave devices. 相似文献