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This research aims to probe the porosity profile and polymerization shrinkage of two different dual cure resin cements with different dentin bonding systems. The self‐adhesive resin cement RelyX U200 (named RU) and the conventional Allcem Core (named AC) were analyzed by x‐ray microtomography (μCT) and Scanning Electron Microscopy (SEM). Each cement was divided into two groups (n = 5): dual‐cured (RUD and ACD) and self‐cured (RUC and ACC). μCT demonstrated that the method of polymerization does not influence the porosity profile but the polymerization shrinkage. Fewer concentration of pores was observed for the conventional resin cement (AC), independently the method used for curing the sample. In addition, SEM showed that AC has more uniform surface and smaller particle size. The method of polymerization influenced the polymerization shrinkage, since no contraction for both RUC and ACC was observed, in contrast with results from dual‐cured samples. For RUD and ACD the polymerization shrinkage was greater in the lower third of the sample and minor in the upper third. This mechanical behavior is attributed to the polymerization toward the light. µCT showed to be a reliable technique to probe porosity and contraction due to polymerization of dental cements.  相似文献   
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Chronic kidney disease (CKD) has been recognized as a global public health problem. Despite the current advances in medicine, CKD-associated morbidity and mortality remain unacceptably high. Several studies have highlighted the contribution of inflammation and inflammatory mediators to the development and/or progression of CKD, such as tumor necrosis factor (TNF)-related biomarkers. The inflammation pathway driven by TNF-α, through TNF receptors 1 (TNFR1) and 2 (TNFR2), involves important mediators in the pathogenesis of CKD. Circulating levels of TNFRs were associated with changes in other biomarkers of kidney function and injury, and were described as predictors of disease progression, cardiovascular morbidity, and mortality in several cohorts of patients. Experimental studies describe the possible downstream signaling pathways induced upon TNFR activation and the resulting biological responses. This review will focus on the available data on TNFR1 and TNFR2, and illustrates their contributions to the pathophysiology of kidney diseases, their cellular and molecular roles, as well as their potential as CKD biomarkers. The emerging evidence shows that TNF receptors could act as biomarkers of renal damage and as mediators of the disease. Furthermore, it has been suggested that these biomarkers could significantly improve the discrimination of clinical CKD prognostic models.  相似文献   
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Integration in the world of sport is one way for individuals with disabilities or motor disorders to feel more socially integrated, independent, and confident. Boccia is a Paralympic sport, which is increasingly getting more attention around the world. These facts have contributed to the objectives of this work. Including it in the serious games category enables to develop and rehabilitate the cognitive capabilities. The main focus was BC3 classification athletes (users with limited motor characteristics that require the use of an assistive device—a ramp, in this case). This paper describes a realistic Boccia game simulator adapted for people with disabilities that integrates a set of features that includes real physics and social features. These features can be used to enhance the interest of nonpractitioners of the sport and to improve the training conditions. The official Boccia regulation was added to the design of the simulator. The usability and approximation to the reality of the simulator were tested and validated based on the tests performed and data collected via a survey of users with no motor or psychological disorders. Realism and usability rating was almost excellent, and good results were achieved at the assessment of the game experience.  相似文献   
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Peltier cooled CdTe detectors have good efficiency beyond the range of energies normally covered by Si(Li) detectors, the most common detectors in PIXE applications. An important advantage of CdTe detectors is the possibility of studying K X-rays lines instead the L X-rays lines in various cases since CdTe detectors present an energy efficiency plateau reaching 70 keV or more. The ITN CdTe useful energy range starts at K-Kα (3.312 keV) and goes up to 120 keV, just above the energy of the lowest γ-ray of the 19F(p, p’γ)19F reaction. In the new ITN HRHE-PIXE line, a CdTe detector is associated to a POLARIS microcalorimeter X-ray detector built by Vericold Technologies GmbH (an Oxford Instruments Group Company). The ITN POLARIS has a resolution of 15 eV at 1.486 keV (Al-Kα) and 24 eV at 10.550 keV (Pb-Lα1). In the present work, a TbCoFe thin film deposited on a Si substrate was analysed at the HRHE-PIXE system. The good efficiency of the CdTe detector at 45 keV (Tb-Kα), and the excellent resolution of POLARIS microcalorimeter at 6.403 keV (Fe-Kα), are presented and the new possibilities open to the IBA analysis of systems with traditionally overlapping X-rays and near mass elements are discussed.  相似文献   
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The impact of supplemental energy on nutrient utilization, fiber digestion, rumen fermentation, and lactation performance was evaluated in dairy cows grazing pastures composed of brome, orchardgrass, red clover, and alfalfa. Three amounts [0, 5, and 10 kg dry matter (DM)/d] of ground dry shelled corn-based concentrate were supplemented to nine rumen cannulated Holstein cows in a 3 x 3 Latin square replicated three times. Cows were on average 84+/-13 d in milk and producing 41.6+/-5.9 kg of milk/d at the beginning of the study. An increase in amounts of concentrate in the diets was associated with an increase in milk production, solids-corrected milk, and concentrations of milk protein and SNF. Milk fat percentage and milk urea nitrogen concentration decreased linearly with supplementation. Milk production and protein percentage were 21.8, 26.8, and 30.4 kg/d, and 2.85, 2.95, and 3.05% for the increasing levels of concentrate, respectively. Intake and digestibility of DM and organic matter (OM) increased as grain supplementation increased. Ruminal pH and total volatile fatty acid concentration (VFA) were not affected by supplementation or the amount of concentrate. Ruminal ammonia concentration was reduced by supplementation, presumably due to a decrease in N intake and greater use of ammonia-N for rumen microbial protein synthesis. Rumen fermentation varied throughout the day, with lower mean pH and higher VFA concentrations at night. Supplementation increased total OM intake, decreased forage OM intake, and increased the proportion of OM that was digested in the intestines. Total DM intake by grazing dairy cows can be increased using ground dry shelled corn-based concentrate without causing negative effects on forage digestion.  相似文献   
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