The feasibility of joining 1.6‐mm‐thick sheets of AA2198‐T8 by the novel friction spot welding technology and the resulting microstructural features on the welds cross sections were assessed, with ...further evaluation of the process parameters on the weld performance. Besides the intrinsic discontinuity related to the interface between the sheets, the hook feature was found to be inherent to the welding process, and its morphology was determinant to the weld performance and fracture mode. A beneficial response on the shear strength was achieved with the minimization of the hook feature because of the absence of a potential site for crack nucleation, although the generation of other defects, depending on the combination of parameters, could erase this benefit. Through statistical analysis, the most influent parameters on the weld performance were plunge depth and welding time. In the present study, regardless of the weld discontinuities, the optimum shear strength revealed a satisfactory performance in mechanical terms for aerospace applications.
Highlights ► CAPE protects against the dopaminergic neuronal loss induced by 6-OHDA in rats. ► This is the first study to show the protection against 6-OHDA neurotoxicity in vivo. ► The mechanism ...involves ROS scavenging, metals chelation and MPT inhibition. ► CAPE does not affect mitochondrial calcium homeostasis. ► CAPE does not cause mitochondrial dysfunction.
The aim of this study was to investigate the reproductive, biochemical, and hematological outcomes of pregnant rats exposed to protein restriction. Wistar rat dams were fed a control normal-protein ...(NP, 17% protein, n=8) or a low-protein (LP, 8% protein, n=14) diet from the 1st to the 20th day of pregnancy. On the 20th day, the clinical signs of toxicity were evaluated. The pregnant rats were then anesthetized and blood samples were collected for biochemical-hematological analyses, and laparotomy was performed to evaluate reproductive parameters. No sign of toxicity, or differences (P>0.05) in body weight gain and biochemical parameters (urea, creatinine, albumin, globulin, and total protein) between NP and LP pregnant dams were observed. Similarly, hematological data, including red blood cell count, white blood cell count, hemoglobin, hematocrit, red blood cell distribution width (coefficient of variation), mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, % lymphocytes, absolute lymphocyte count, platelet count, and mean platelet volume were similar (P>0.05) at the end of pregnancy. Reproductive parameters (the dam-offspring relationship, ovary mass, placenta mass, number of corpora lutea, implantation index, resorption index, and the pre- and post-implantation loss rates) were also not different (P>0.05) between NP and LP pregnant dams. The present data showed that a protein-restricted diet during pregnancy did not alter reproductive, biochemical, and hematological parameters and seems not to have any toxic effect on pregnant Wistar rats.
In this work boron-doped diamond (BDD) films were grown on new geometric form substrate. A laser texturized pretreatment on these substrates has promoted a better adherence between film and ...substrate, and a decrease of diamond total stress. Films morphology, obtained from Scanning Electron Microscopy (SEM) images, have showed that diamond average grain size, between 10–15 μm, decreased when the boron doping level was increased. For the micro-Raman spectroscopy, spectra analyses performed on each sample have allowed the residual stress evaluation and the diamond purity, from diamond and graphitic Raman peaks shifts. In these films, residual stress increased from 0.2 to 1.2 GPa and diamond purity decreased from 99.6% to 92.6% as the doping level increased.
A specific study of morphology, total stress and diamond purity as a function of methane concentration was done for diamond film doped with 10,000 ppm B
/
C. It was observed a significant increase of grain size and total stress but little variation of diamond purity as methane concentration was increased. All these results gave us support for the use of these devices in different applications.
Studies have shown that autologous hematopoietic SCT (HSCT) can be used as an intensive immunosuppressive therapy to treat refractory patients and to prevent the progression of multiple sclerosis ...(MS). This is a prospective multicentric Brazilian MS trial comparing two conditioning regimens: BEAM/horse ATG and CY/rabbit ATG. Most (80.4%) of the 41 subjects in the study had the secondary progressive MS subtype and the mean age was 42 years. The baseline EDSS score in 58.5% of the subjects was 6.5 and 78% had a score of 6.0 or higher, respectively. The complication rate during the intra-transplantation period was 56% for all patients: 71.4% of the patients in the BEAM/hATG group and 40% in the CY/rATG group (P=0.04). Three subjects (7.5%) died of cardiac toxicity, sepsis and alveolar hemorrhage, all of them in the BEAM/ATG group. EFS was 58.54% for all patients: 47% in the BEAM/hATG group and 70% in the CY/rATG group (P=0.288). In conclusion, the CY/rATG regimen seems to be associated with similar outcome results, but presented less toxicity when compared with the BEAM/hATG regimen. Long-term follow-up would be required to fully assess the differences in therapeutic effectiveness between the two regimens.
Aluminum (Al) tolerance mechanisms in crop plants have been extensively researched, but our understanding of the physiological mechanisms underlying Al tolerance in trees is still limited. To ...investigate Al tolerance in eucalypts, seedlings of six species (Eucalyptus globulus Labill., Eucalyptus urophylla S.T. Blake, Eucalyptus dunnii Maiden, Eucalyptus saligna Sm., Eucalyptus cloeziana F. J. Muell. and Eucalyptus grandis w. Hill ex Maiden) and seedlings of six clones of Eucalyptus species were grown for 10 days in nutrient solutions containing Al concentrations varying from 0 to 2.5 micromolar (0 to 648 micromolar Al(3+) activities). Root elongation of most species was inhibited only by high Al(3+) activities. Low to intermediate Al(3+) activities were beneficial to root elongation of all species and clones. Among the species tested, E. globulus and E. urophylla were more tolerant to Al toxicity, whereas E. grandis and E. cloeziana were more susceptible to Al-induced damage. Although E. globulus seedlings were tolerant to Al toxicity, they were highly sensitive to lanthanum (La), indicating that the tolerance mechanism is specific for Al. Fine roots accumulated more Al and their elongation was inhibited more than that of thick roots. In E. globulus, accumulation of Al in root tips increased linearly with increasing Al concentration in the nutrient solution. The majority of Al taken up was retained in the root system, and the small amounts of Al translocated to the shoot system were found mainly in older leaves. No more than 60% of the Al in the thick root tip was in an exchangeable form in the apoplast that could be removed by sequential citrate rinses. Gas chromatography/mass spectrometry and ion chromatography analyses indicated that root exposure to Al led to a greater than 200% increase in malic acid concentration in the root tips of all eucalypt species. The increase in malate concentration in response to Al treatment correlated with the degree of Al tolerance of the species. A small increase in citric acid concentration was also observed in all species, but there were no consistent changes in the concentrations of other organic acids in response to Al treatment. In all eucalypt species, Al treatment induced the secretion of citric and malic acid in root exudates, but no trend with respect to Al tolerance was observed. Thus, although malate and citrate exudation by roots may partially account for the overall high Al tolerance of these eucalypt species, it appears that tolerance is mainly derived from the internal detoxification of Al by complexation with malic acid.
This work investigated the melting and nonisothermal melt crystallization of poly (butylene terephthalate) (PBT) and poly ( -caprolactone) (PCL) blends with PCL content ranging from 3 to 10% of the ...weight. Thermal stability and morphology analyses were performed by thermogravimetry (TG) and scanning electron microscopy (SEM), whereas the nonisothermal crystallization of PBT/PCL blends carried out by differential scanning calorimetry (DSC), and the kinetic parameters were determined using Pseudo-Avrami, Ozawa and Mo models. PCL improved thermal stability by decreasing the degradation rate of PBT. From SEM images the brittle fracture of PBT was modified through PCL addition with absorption energy mechanisms developed in PBT/PCL blends. PCL delayed the melt crystallization of PBT, most due to its fluid viscous state during PBT crystallization. Ozawa model failed to provide an effective description of the blends, while Pseudo-Avrami and Mo models successfully described the nonisothermal melt crystallization, and linearity deviations were observed only at the beginning and at the end of crystallization, probably due to nucleation and spherulite impingement during secondary crystallization.
We report here the first six cases of leprosy associated with HLA-identical allogeneic SCT in different phases and with different findings and outcomes. Skin and peripheral nerves may be sites of ...leprosy associated with SCT, stressing the importance of differential diagnosis between leprosy and GVHD or drug reactions. Clinical manifestations of leprosy before or after transplantation did not influence the outcome of SCT in our cases.
•Review of the macromodel methods under development used in the Brazilian System.•Real-time and offline practical application examples.•Brazilian Power System Operator’s experience with FDNEs for ...real-time simulations.•Brazilian Electrical Energy Research Center’s experience with FDNEs for EMT studies.
This paper presents a qualitative overview of the main developments carried out by the Brazilian Electrical Energy Research Center and the Brazilian Power System Operator to provide tools to assembly Frequency Dependent Network Equivalents. These equivalents have fundamental importance in the electromagnetic transient studies in the Brazilian Interconnected Power System. Applications for these studies in offline and real-time simulation environments are also presented, using the ATP and the HYPERSIM, respectively.
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