68 resultados para 124-777B
Resumo:
Copper coatings containing well-distributed Nb particles were obtained by co-electrodeposition in an acidic sulfate bath. Nb particle concentration in the bath was the most significant factor for the incorporation of Nb particles in copper, followed by stirring rate, whereas current density presented low significance. High Nb particle concentration and low stirring rate led to a higher incorporated Nb particle content. The microhardness of the composite layers was higher than that of pure copper deposits obtained under the same conditions due to copper matrix grain refinement and increased with the increase of both current density and incorporated Nb particle volume fraction. The corrosion resistance of Cu-Nb composites in 0.5 wt.% H(2)SO(4) solution at room temperature was higher than that of pure copper and increased with the increase of the Nb content. (C) 2010 Elsevier B.V. All rights reserved.
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This study assessed the quality of life (QoL) of 124 people with coronary artery disease who had coronary artery bypass surgery in a hospital in Brazil, by using the Modified Flanagan`s QoL instrument as the outcome measure. In addition, we studied the association between QoL and demographic, clinical, and perceived health status (using SF-36 Health Survey) measures. The mean for the Modified Flanagan`s QoL was high (M = 84.8, SD = 13.6) when compared to similar studies in the United States. In a linear regression analysis, the SF-36 subscales of vitality, and general and mental health were statistically significant (p < .01 for all), after adjusting for other demographic and clinical variables. Increasing values of those SF-36 subscales corresponded to increasing Modified Flanagan`s QoL. Despite the limitations of the study, this result suggests that future clinical interventions aimed to improve QoL in this population could focus on the patient`s psychological conditions after the surgery.
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Study design: Evaluation of knees of tetraplegic patients who have been walking for several months with the aid of a system that involves neuromuscular stimulation, treadmill and a harness support device. Objectives: To investigate if the training program could cause knee injury to tetraplegic patients. Setting: Hospital das Clinicas - UNICAMP. Campinas-SP, Brazil. Methods: Nine patients were evaluated. Clinical exam and magnetic resonance images (MRIs) were used for evaluation. MRIs were taken before and after the training program, in a 6-month interval for each patient. There were two sessions of training every week. Each session lasted 20 min. Results: No severe clinical abnormality was observed in any patient. Mild knee injury was observed in four of nine patients studied. Conclusions: Tetraplegic patients undergoing treadmill gait training deserve a close follow-up to prevent knee injury.
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An updated flow pattern map was developed for CO2 on the basis of the previous Cheng-Ribatski-Wojtan-Thome CO2 flow pattern map [1,2] to extend the flow pattern map to a wider range of conditions. A new annular flow to dryout transition (A-D) and a new dryout to mist flow transition (D-M) were proposed here. In addition, a bubbly flow region which generally occurs at high mass velocities and low vapor qualities was added to the updated flow pattern map. The updated flow pattern map is applicable to a much wider range of conditions: tube diameters from 0.6 to 10 mm, mass velocities from 50 to 1500 kg/m(2) s, heat fluxes from 1.8 to 46 kW/m(2) and saturation temperatures from -28 to +25 degrees C (reduced pressures from 0.21 to 0.87). The updated flow pattern map was compared to independent experimental data of flow patterns for CO2 in the literature and it predicts the flow patterns well. Then, a database of CO2 two-phase flow pressure drop results from the literature was set up and the database was compared to the leading empirical pressure drop models: the correlations by Chisholm [3], Friedel [4], Gronnerud [5] and Muller-Steinhagen and Heck [6], a modified Chisholm correlation by Yoon et al. [7] and the flow pattern based model of Moreno Quiben and Thome [8-10]. None of these models was able to predict the CO2 pressure drop data well. Therefore, a new flow pattern based phenomenological model of two-phase flow frictional pressure drop for CO2 was developed by modifying the model of Moreno Quiben and Thome using the updated flow pattern map in this study and it predicts the CO2 pressure drop database quite well overall. (C) 2007 Elsevier Ltd. All rights reserved.
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Several mining companies operating in Brazil have been preparing mine closure plans describing end of life actions to ensure long term physical stability, land rehabilitation and, to a certain extent, socioeconomic measures. Most Brazilian and international guidelines, however, skip early closure and only feature guidance to closure planning after reserve depletion. In this paper, two cases of early closure in Australia are reviewed, causes for early closure are explored, criteria to evaluate preparedness to early mine closure are proposed and tested in two mines. It concludes that, despite recent advances, planning for mine closure seldom take account of early closure risks.
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This paper addresses the single machine scheduling problem with a common due date aiming to minimize earliness and tardiness penalties. Due to its complexity, most of the previous studies in the literature deal with this problem using heuristics and metaheuristics approaches. With the intention of contributing to the study of this problem, a branch-and-bound algorithm is proposed. Lower bounds and pruning rules that exploit properties of the problem are introduced. The proposed approach is examined through a computational comparative study with 280 problems involving different due date scenarios. In addition, the values of optimal solutions for small problems from a known benchmark are provided.
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Chitinase and peroxidase activity in different stages of eucalypt leaves after inoculation with Puccinia psidii and acibenzolar-S-metil To elucidate some biochemical processes during infection in the pathosystem Puccinia psidii x eucalyptus, the defense metabolism in different-stage leaves was compared between rust-resistant and susceptible clones, respectively. In addition, chitinase and peroxidase activities were assayed. Each treatment consisted of 4 replicates, in a completely randomized design: 2 clones, inoculated and not inoculated with P. psidii; sprayed with acibenzolar-S-methyl (ASM) and distilled water; and represented by the 1(st) leaf pair (size equivalent to 1/5 total leaf development), 2(nd) pair (2/5 total development), and 4(th) pair (4/5 total leaf length). Leaves were harvested in 4 periods: 0, 24, 72 and 96 hours after inoculation. Results indicated that ASM treatment or P. psidii action led to higher chitinase and peroxidase activity level but did not alter the expression of these activities in developed leaves (4(th) pair) during the experiment. Alterations in enzyme levels after inoculation were only observed in developing leaves (1(st) and 2(nd) pairs), which suggests that the response to infection was concomitant to chitinase and peroxidase synthesis. The highest increases in enzymatic activities were observed in resistant clones at 72 hours after inoculation and in susceptible ones previously treated with ASM and later inoculated with the pathogen.
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The combined effect of temperature (15A degrees C, 20A degrees C, 25A degrees C, 30A degrees C, 35A degrees C, 40A degrees C and 42A degrees C) and leaf wetness duration (0, 4, 8 12, 16, 20 and 24 h) on infection and development of Asiatic citrus canker (Xanthomonas citri subsp. citri) on Tahiti lime plant was examined in growth chambers. No disease developed at 42A degrees C and zero hours of leaf wetness. Periods of leaf wetness as short as 4 h were sufficient for citrus canker infection. However, a longer leaf duration wetness (24 h) did not result in much increase in the incidence of citrus canker, but led to twice the number of lesions and four times the disease severity. Temperature was the greatest factor influencing disease development. At optimum temperatures (25-35A degrees C), there was 100% disease incidence. Maximum disease development was observed at 30-35A degrees C, with up to a 12-fold increase in lesion density, a 10-fold increase in lesion size and a 60-fold increase in disease severity.
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The rhizosphere is a niche exploited by a wide variety of bacteria. The expression of heterologous genes by plants might become a factor affecting the structure of bacterial communities in the rhizosphere. In a greenhouse experiment, the bacterial community associated to transgenic eucalyptus, carrying the Lhcb1-2 genes from pea (responsible for a higher photosynthetic capacity), was evaluated. The culturable bacterial community associated to transgenic and wild type plants were not different in density, and the Amplified Ribosomal DNA Restriction Analysis (ARDRA) typing of 124 strains revealed dominant ribotypes representing the bacterial orders Burkholderiales, Rhizobiales, and Actinomycetales, the families Xanthomonadaceae, and Bacillaceae, and the genus Mycobacterium. Principal Component Analysis based on the fingerprints obtained by culture-independent Denaturing Gradient Gel Electrophoresis analysis revealed that Alphaproteobacteria, Betaproteobacteria and Actinobacteria communities responded differently to plant genotypes. Similar effects for the cultivation of transgenic eucalyptus to those observed when two genotype-distinct wild type plants are compared.
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Several studies using transrectal ovarian ultrasonic scanning in Bos taurus (B. taurus) cattle and more recently in Bos indicus (B. Indicus) females evaluated the reproductive cycles of heifers and cows under different conditions. In general, B. indicus cattle have more follicles and more follicular waves during the estrous cycle and ovulate from smaller follicles than B. taurus. Consequently B. indicus females have smaller corpora lutea and it is assumed circulating concentrations of estradiol and progesterone are also less. However, these findings may vary depending on the nutritional status and regimen in which the animals are managed. Moreover, there are significant differences between B. taurus and B. indicus regarding follicle size at the time of deviation of the dominant follicle. These differences in ovarian function between B. indicus and B. taurus, e.g. greater antral follicle population are, probably, the main reasons for the great success of in vitro embryo production programs in Zebu cattle, especially in Brazil. (C) 2011 Elsevier B.V. All rights reserved.
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Glycoproteins from the total vesicular fluid of Taenia crassiceps (VF-Tc) were prepared using three different purification methods, consisting of ConA-lectin affinity chromatography (ConA-Tc), preparative electrophoresis (SDS-PAGE) (14gp-Tc), and monoclonal antibody immunoaffinity chromatography (18/14-Tc). The complex composition represented by the VF-Tc and ConA-Tc antigens revealed peptides ranging from 101 - to 14-kDa and from 92- to 12-kDa, respectively. Immunoblotting using lectins confirmed glucose/mannose (glc/man) residues in the 18- and 14-kDa peptides, which are considered specific and immunodominant for the diagnosis of cysticercosis, and indicated that these fractions are glycoproteins. Serum antibodies from a patient with neurocysticercosis that reacted to the 14gp band from T. crassiceps (Tc) were eluted from immunoblotting membranes and showed reactivity to 14gp from Taenia solium. In order to determine the similar peptide sequence, the N-terminal amino acid was determined and analyzed with sequences available in public databases. This sequence revealed partial homology between T. crassiceps and T solium peptides. In addition, mass spectrometry along with theoretical M(r) and pI of the 14gp-Tc point suggested a close relationship to some peptides of a 150-kDa protein complex of the T solium previously described. The identification of these common immunogenic sites will contribute to future efforts to develop recombinant antigens and synthetic peptides for immunological assays. (C) 2009 Elsevier Inc. All rights reserved.
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Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), Brazil[2008/54131-0]
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Although the origin and functions of B-1 cells are controversial, they are considered as a cellular element of innate immunity due to their ability to produce natural autoantibodies of the IgM type. These antibodies are encoded by a relatively limited repertoire of V genes, and their resulting diversity is smaller than that produced by conventional B cells. B-1 cells constitute the larger fraction of B cells in the peritoneal cavity and migrate to non-specific inflammation sites. In addition, they contribute to the production of IgA antibodies in the intestinal lamina propria. It has been demonstrated that they participate in the induction and maintenance of peripheral tolerance. Herein, the participation of B-1 cells in inducing oral tolerance is evaluated. Unexpectedly, BALB/Xid mice, the animals deficient in B-1 cells, are not tolerized to OVA but instead are responsive to oral immunization. Conversely, BALB/c mice respond to oral tolerance to this antigen. We used these biological characteristics of these animals to investigate whether BA cells are involved in the induction of oral tolerance to OVA. Results show that B-1 cells from BALB/c mice, treated orally with OVA and adoptively transferred to BALB/Xid mice were able to suppress local hypersensitivity reaction and lymphoproliferative cellular response observed in BALB/.Xid mice. These data demonstrate that B-1 cells have regulatory properties and are involved in the induction of oral tolerance. (C) 2009 Elsevier B.V. All rights reserved.
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Background: The transcription factors SREBP1 and SCAP are involved in intracellular cholesterol homeostasis. Polymorphisms of these genes have been associated with variations on serum lipid levels and response to statins that are potent cholesterol-lowering drugs. We evaluated the effects of atorvastatin on SREBF1a and SCAP mRNA expression in peripheral blood mononuclear cells (PBMC) and a possible association with gene polymorphisms and lowering-cholesterol response. Methods: Fifty-nine hypercholesterolemic patients were treated with atorvastatin (10 mg/day for 4 weeks). Serum lipid profile and mRNA expression in PBMC were assessed before and after the treatment. Gene expression was quantified by real-time PCR using GAPD as endogenous reference and mRNA expression in HepG2 cells as calibrator. SREBF1 -36delG and SCAP A2386G polymorphisms were detected by PCR-RFLP. Results: Our results showed that transcription of SREBF1a and SCAP was coordinately regulated by atorvastatin (r=0.595, p<0.001), and that reduction in SCAP transcription was associated with the 2386AA genotype (p=0.019). Individuals who responded to atorvastatin with a downregulation of SCAP had also a lower triglyceride compared to those who responded to atorvastatin with an upregulation of SCAP. Conclusion: Atorvastatin has differential effects on SREBF1a and SCAP mRNA expression in PBMC that are associated with baseline transcription levels, triglycerides response to atorvastatin and SCAP A2386G polymorphism. (c) 2008 Elsevier B.V. All rights reserved.
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Assortments of biophysical methods are used to the study the stratum corneum morphology and dynamic with the objective to elucidate the correlation between its structure and functions. Among these methods, there are: X-ray diffraction, electron paramagnetic resonance, differential scanning calorimetry, Raman spectroscopy with Fourrier transform, infrared spectroscopy and photoacustic spectroscopy. In this manuscript, methods are presented and discussed in relation to the use indication, interpretation of results and advantages and limitations to the stratum corneum analysis.