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121.
Martins CH Carvalho TC Souza MG Ravagnani C Peitl O Zanotto ED Panzeri H Casemiro LA 《Journal of materials science. Materials in medicine》2011,22(6):1439-1446
This study assessed the antimicrobial activity of a new bioactive glass–ceramic (Biosilicate®) against anaerobic, microaerophilic, and facultative anaerobic microorganisms. Evaluation of the antimicrobial activity was carried out by three methods, namely agar diffusion, direct contact, and minimal inhibitory concentration (MIC). For the agar diffusion technique, bio glass–ceramic activity was observed against various microorganisms, with inhibition haloes ranging from 9.0 ± 1.0 to 22.3 ± 2.1 mm. For the direct contact technique, Biosilicate® displayed activity against all the microorganisms, except for S. aureus. In the first 10 min of contact between the microorganisms and Biosilicate®, there was a drastic reduction in the number of viable cells. Confirming the latter results, MIC showed that the Biosilicate® inhibited the growth of microorganisms, with variations between ≤ 2.5 and 20 mg/ml. The lowest MIC values (7.5 to ≤ 2.5 mg/ml) were obtained for oral microorganisms. In conclusion, Biosilicate® exhibits a wide spectrum of antimicrobial properties, including anaerobic bacteria. 相似文献
122.
The objective of this study is to explore the association between pork as the main meal component and the choice for side dishes and beverages depending on foodscape and individual characteristics, including overweight and obesity among fresh pork consumers (n = 2156) in five European countries (Belgium, Denmark, Germany, Greece and Poland). Males were found to combine pork more with caloric drinking (odds ratio = 1.32) and low levels of vegetable intake (odds ratio = 1.32) compared to females. Younger consumers were more likely to combine pork with low levels of vegetable intake but less likely to combine pork with sauces or condiments. Heavy users of pork were more likely (odds ratio = 1.43) to combine pork with sauces or condiments. The study also found an association between being overweight or obese and higher consumption of carbohydrate rich staple foods (odds ratio = 1.30) and caloric drinks (odds ratio = 1.30) as side dishes to pork meat. Substantial cross-cultural differences were revealed in line with typical pork consumption and meal composition habits in the respective countries. Finally, this study found that the company of family plays a significant role when choosing side dishes for pork as meal center, thus constituting a relevant venue for the positioning and marketing of pork, as well as for future public health information about meals with pork as main meal component. 相似文献
123.
124.
Partial discharge signal denoising with spatially adaptive wavelet thresholding and support vector machines 总被引:1,自引:0,他引:1
Hilton de Oliveira Mota Leonardo Chaves Dutra da Rocha Thiago Cunha de Moura Salles 《Electric Power Systems Research》2011,81(2):644-659
In this paper an improved method to denoise partial discharge (PD) signals is presented. The method is based on the wavelet transform (WT) and support vector machines (SVM) and is distinct from other WT-based denoising strategies in the sense that it exploits the high spatial correlations presented by PD wavelet decompositions as a way to identify and select the relevant coefficients. PD spatial correlations are characterized by WT modulus maxima propagation along decomposition levels (scales), which are a strong indicative of the their time-of-occurrence. Denoising is performed by identification and separation of PD-related maxima lines by an SVM pattern classifier. The results obtained confirm that this method has superior denoising capabilities when compared to other WT-based methods found in the literature for the processing of Gaussian and discrete spectral interferences. Moreover, its greatest advantages become clear when the interference has a pulsating or localized shape, situation in which traditional methods usually fail. 相似文献
125.
Renato C. Dutra 《Information Processing Letters》2006,98(4):139-144
We consider networks of anonymous sensors and address the problem of constructing routes for the delivery of information from a group of sensors in response to a query by a sink. In order to circumvent the restrictions imposed by anonymity, we rely on using the power level perceived by the sensors in the query from the sink. We introduce a simple distributed algorithm to achieve the building of routes to the sink and evaluate its performance by means of simulations. 相似文献
126.
R. C. L. Dutra V. L. Lourenço M. F. Diniz M. F. P. Azevedo R. V. Barbosa B. G. Soares 《Polymer Bulletin》1996,36(5):593-600
Summary A quantitative method for the determination of vinyl mercaptoacetate (VMA) in poly(ethylene-co-vinyl alcohol-co-vinyl mercaptoacetate) (EVALSH) based on Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) was developed. A plot of relative absorbance values (A1736/A720) versus esterification degree in EVALSH samples determined by TGA analysis revealed a good linear relationship. 相似文献
127.
J.B Malchaire N.A Cock A Piette R Dutra Leao M Lara F Amaral 《International Journal of Industrial Ergonomics》1997,19(6):471-482
A 2-year prospective study was conducted on 184 workers about the relationship between the development of musculoskeletal wrist disorders (WD) and the occupational constraint parameters at their job (wrist angles, forces, repetitiveness and angular velocities), taking into account personal and occupational confounding factors. The results demonstrate a greater probability of developing WD for the workers suffering from chronic diseases, from psychological disorders, practising a sport involving the upper limbs and judging their work tiring.All occupational constraint factors are correlated except for the angles. Logistic correlation analyses show that the most significant associations with a greater probability of developing WD are observed for the mean relative EMG value recorded on the finger and hand flexors and the time during which the velocity in flexion–extension is greater than 50°/s. None of the angular parameters shows any association.Relevance to industryThe study shows that the main factor on which to act in order to reduce the risk of WD is clearly the forces exerted by the hand.The objective of the control measures should be to reduce the muscular activity of the finger and hand flexors below 15% of the maximum activity corresponding to the maximum voluntary contraction of the finger flexors.A reduction of these forces appears to be associated with a reduction of the angular velocities of the wrist and of the repetitiveness. 相似文献
128.
Alessandra Cremasco André Dutra Messias Andrea Rodrigues Esposito Eliana Aparecida de Rezende Duek Rubens Caram 《Materials science & engineering. C, Materials for biological applications》2011,31(5):833-839
Titanium alloys, especially β-type alloys containing β-stabilizing elements, constitute a highly versatile category of metallic materials that have been under constant development for application in orthopedics and dentistry. This type of alloy generally presents a high mechanical strength-to-weight ratio, excellent corrosion resistance and low elastic modulus. The purpose of this study is to evaluate the cytotoxicity and adhesion of fibroblast cells on titanium alloy substrates containing Nb, Ta, Zr, Cu, Sn and Mo alloying elements. Cells cultured on polystyrene were used as controls. In vitro results with Vero cells demonstrated that the tested materials, except Cu-based alloy, presented high viability in short-term testing. Adhesion of cells cultured on disks showed no differences between the materials and reference except for the Ti–Cu alloy, which showed reduced adhesion attributed to poor metabolic activity. Titanium alloys with the addition of Nb, Ta, Zr, Sn and Mo elements show a promising potential for biomedical applications. 相似文献
129.
JR Meyer-Fernandes PM Dutra CO Rodrigues J Saad-Nehme AH Lopes 《Canadian Metallurgical Quarterly》1997,341(1):40-46
Variation in the level of fetal hemoglobin (HbF) accounts for much of the clinical heterogeneity observed in patients with sickle cell disease (SCD). The HbF level has emerged as an important prognostic factor in both sickle cell pain and mortality, and a % HbF of 10-20% has been suggested as a threshold level for diminished clinical severity. The number of erythrocytes that contain HbF (termed F cells) may also be critically important, as F cells resist intravascular sickling and have preferential in vivo survival. Since F cells can be enumerated with high accuracy using flow cytometry methods, we prospectively studied a cohort of 242 children with SCD. Children with HbS and hereditary persistence of fetal hemoglobin (S/HPFH) had essentially 100% F cells. In contrast, children with homozygous sickle cell anemia (HbSS), HbS/beta0 thalassemia, or HbS/beta+ thalassemia had significantly lower mean % F cell values (55.9, 61.6, and 51.3%, respectively; P < 0.001), and children with HbSC had even fewer F cells (27.0%; P < 0.001). There was a highly significant correlation between the % F cells and the log (% HbF), which was observed for the total population of children (r = 0.95, P < 0.001), as well as for each of the individual subgroups of children with HbSS (r = 0.94, P < 0.001), HbSC (r = 0.89, P < 0.001), or HbS/beta0 thalassemia and HbS/beta+ thalassemia (r = 0.95, P <0.001). This logarithmic correlation between % F cells and % HbF has not been previously described and has important implications for the pharmacologic manipulation of HbF in patients with SCD. 相似文献
130.