14 resultados para e-3 value

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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In this work, we report the construction of potential energy surfaces for the (3)A '' and (3)A' states of the system O(P-3) + HBr. These surfaces are based on extensive ab initio calculations employing the MRCI+Q/CBS+SO level of theory. The complete basis set energies were estimated from extrapolation of MRCI+Q/aug-cc-VnZ(-PP) (n = Q, 5) results and corrections due to spin-orbit effects obtained at the CASSCF/aug-cc-pVTZ(-PP) level of theory. These energies, calculated over a region of the configuration space relevant to the study of the reaction O(P-3) + HBr -> OH + Br, were used to generate functions based on the many-body expansion. The three-body potentials were interpolated using the reproducing kernel Hilbert space method. The resulting surface for the (3)A '' electronic state contains van der Waals minima on the entrance and exit channels and a transition state 6.55 kcal/mol higher than the reactants. This barrier height was then scaled to reproduce the value of 5.01 kcal/mol, which was estimated from coupled cluster benchmark calculations performed to include high-order and core-valence correlation, as well as scalar relativistic effects. The (3)A' surface was also scaled, based on the fact that in the collinear saddle point geometry these two electronic states are degenerate. The vibrationally adiabatic barrier heights are 3.44 kcal/mol for the (3)A '' and 4.16 kcal/mol for the (3)A' state. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4705428]

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This work develops a computational approach for boundary and initial-value problems by using operational matrices, in order to run an evolutive process in a Hilbert space. Besides, upper bounds for errors in the solutions and in their derivatives can be estimated providing accuracy measures.

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Autoantibodies in early rheumatoid arthritis (RA) have important diagnostic value. The association between the presence of autoantibodies against cyclic citrullinated peptide and the response to treatment is controversial. To prospectively evaluate a cohort of patients with early rheumatoid arthritis (< 12 months of symptoms) in order to determine the association between serological markers (rheumatoid factor (RF), anti-citrullinated protein antibodies) such as anti-cyclic citrullinated peptide antibodies (anti-CCP) and citrullinated anti-vimentin (anti-Sa) with the occurrence of clinical remission, forty patients diagnosed with early RA at the time of diagnosis were evaluated and followed for 3 years, in use of standardized therapeutic treatment. Demographic and clinical data were recorded, disease activity score 28 (DAS 28), as well as serology tests (ELISA) for RF (IgM, IgG, and IgA), anti-CCP (CCP2, CCP3, and CCP3.1) and anti-Sa in the initial evaluation and at 3, 6, 12, 18, 24, and 36 months of follow-up. The outcome evaluated was the percentage of patients with clinical remission, which was defined by DAS 28 lower than 2.6. Comparisons were made through the Student t test, mixed-effects regression analysis, and analysis of variance (significance level of 5%). The mean age was 45 years, and a female predominance was observed (90%). At the time of diagnosis, RF was observed in 50% of cases (RF IgA-42%, RF IgG-30%, and RF IgM-50%), anti-CCP in 50% (no difference between CCP2, CCP3, and CCP3.1) and anti-Sa in 10%. After 3 years, no change in the RF prevalence and anti-CCP was observed, but the anti-Sa increased to 17.5% (P = 0.001). The percentage of patients in remission, low, moderate, and intense disease activity, according to the DAS 28, was of 0, 0, 7.5, and 92.5% (initial evaluation) and 22.5, 7.5, 32.5, and 37.5% (after 3 years). There were no associations of the presence of autoantibodies in baseline evaluation and in serial analysis with the percentage of clinical remission during follow-up of 3 years The presence of autoantibodies in early RA has no predictive value for clinical remission in early RA.

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The demand for "welfare friendly" products increases as public conscience and perception on livestock production systems grow. The public and policy-makers demand scientific information for education and to guide decision processes. This paper describes some of the last decade contributions made by scientists on the technical, economical and market areas of farm animal welfare. Articles on animal welfare were compiled on the following themes: 1) consumer behavior, 2) technical and economical viability, 3) public regulation, and 4) private certification policies. Most studies on the economic evaluation of systems that promote animal welfare involved species destined to produce export items, such as eggs, beef and pork. Few studies were found on broilers, dairy cows and fish, and data regarding other species, such as horses, sheep and goats were not found. Scientists understand that farm animal welfare is not only a matter of ethics, but also an essential tool to gain and maintain markets. However, it is unfortunate that little attention is paid to species that are not economically important for exports. Studies that emphasize on more humane ways to raise animals and that provide economic incentives to the producer are needed. An integrated multidisciplinary approach is necessary to highlight the benefits of introducing animal welfare techniques to existing production systems.

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Objective: Describe the total energy value and percentage contribution of calories from macronutrients in the diet of elderly individuals living in Fortaleza/CE. Methods: This is a population-based, cross-sectional domiciliary study, which included 458 elderly individuals (66.6% women). The variables evaluated were total energy value (TEV) and the percentage contribution of calories from proteins, carbohydrates, and lipids. The results are shown as mean, standard deviation, and percentile distribution (P5, P10, P25, P50, P75, P90, P95). The Student's t-test and analysis of variance (one-way ANOVA) with LSD post-hoc tests were used to determine the statistical significance of means between two groups and among three or more groups, respectively. Results: When comparing the mean values of TEV among categories of socioeconomic and demographic variables, statistically significant differences were found between women for ethnicity, years of schooling and socioeconomic level. Among men, differences were found for years of schooling and socioeconomic level. The mean energy value of men's diet was significantly higher than that of women (1475.8 kcal and 1236.4 kcal, respectively). The mean values of calorie percentage contribution from proteins, carbohydrates, and lipids were similar between men and women. Conclusion: The elderly of this study showed significant differences in mean values of TEV between sexes and between the categories years of schooling and socioeconomic level. Women also showed significant differences between the ethnic categories. The mean relative contribution of macronutrients in TEV was similar between genders and age groups.

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Irnmunohistochcmical expression of BAX was evaluated in 24 canine cutaneous mast cell tumours in order to verify the relationship of this expression to the histopathological grade of the lesions and its prognostic value for clinical outcome. BAX expression increased with higher histopathological grades (P = 0.0148; P < 0.05 between grades I and III). Animals with high levels of BAX expression were 4.25 times more likely to die from the disease and had shorter post-surgical survival times (P = 0.0009). These results suggest that alterations in BAX expression may be related to the aggressiveness of canine cutaneous mast cell tumours, indicating that immunohistochemical detection of BAX may be predictive of clinical outcome. (C) 2011 Elsevier Ltd. All rights reserved.

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The present work is inserted into the broad context of the upgrading of lignocellulosic fibers. Sisal was chosen in the present study because more than 50% of the world's sisal is cultivated in Brazil, it has a short life cycle and its fiber has a high cellulose content. Specifically, in the present study, the subject addressed was the hydrolysis of the sisal pulp, using sulfuric acid as the catalyst. To assess the influence of parameters such as the concentration of the sulfuric acid and the temperature during this process, the pulp was hydrolyzed with various concentrations of sulfuric acid (30-50%) at 70 A degrees C and with 30% acid (v/v) at various temperatures (60-100 A degrees C). During hydrolysis, aliquots were withdrawn from the reaction media, and the solid (non-hydrolyzed pulp) was separated from the liquid (liquor) by filtering each aliquot. The sugar composition of the liquor was analyzed by HPLC, and the non-hydrolyzed pulps were characterized by viscometry (average molar mass), and X-ray diffraction (crystallinity). The results support the following conclusions: acid hydrolysis using 30% H2SO4 at 100 A degrees C can produce sisal microcrystalline cellulose and the conditions that led to the largest glucose yield and lowest decomposition rate were 50% H2SO4 at 70 A degrees C. In summary, the study of sisal pulp hydrolysis using concentrated acid showed that certain conditions are suitable for high recovery of xylose and good yield of glucose. Moreover, the unreacted cellulose can be targeted for different applications in bio-based materials. A kinetic study based on the glucose yield was performed for all reaction conditions using the kinetic model proposed by Saeman. The results showed that the model adjusted to all 30-35% H2SO4 reactions but not to greater concentrations of sulfuric acid. The present study is part of an ongoing research program, and the results reported here will be used as a comparison against the results obtained when using treated sisal pulp as the starting material.

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Poly(3-hydroxybutyrate) (PHB) biosynthesis from soybean oil by Cupriavidus necator was studied using a bench scale bioreactor. The highest cell concentration (83 g l(-1)) was achieved using soybean oil at 40 g l(-1) and a pulse of the same concentration. The PHB content was 81% (w/w), PHB productivity was 2.5 g l(-1) h(-1), and the calculated Y-p/s value was 0.85 g g(-1). Growth limitation and the onset of PHB biosynthesis took place due to exhaustion of P, and probably also Cu, Ca, and Fe.

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MeOH extract from the leaves of Plectranthus barbatus Andrews (Lamiaceae), showed in vitro anti-trypanosomal activity. The bioassay-guided fractionation resulted in the isolation of a gallic acid derivative, identified as 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG), after thorough NMR and MS spectral analysis. Finally, this compound was tested against trypomastigote forms of T. cruzi and displayed an EC50 value of 67 mu M, at least 6.6-fold more effective than the standard drug benznidazole. This is the first occurrence of PGG in the Plectranthus genus and the first anti-parasitic activity described for PGG in the literature.

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Background: This study evaluated a wide range of viral load (VL) thresholds to identify a cut-point that best predicts new clinical events in children on stable highly active antiretroviral therapy (HAART). Methods: Cox proportional hazards modeling was used to assess the adjusted risk for World Health Organization stage 3 or 4 clinical events (WHO events) as a function of time-varying CD4, VL, and hemoglobin values in a cohort study of Latin American children on HAART >= 6 months. Models were fit using different VL cut-points between 400 and 50,000 copies per milliliter, with model fit evaluated on the basis of the minimum Akaike information criterion value, a standard model fit statistic. Results: Models were based on 67 subjects with WHO events out of 550 subjects on study. The VL cut-points of >2600 and >32,000 copies per milliliter corresponded to the lowest Akaike information criterion values and were associated with the highest hazard ratios (2.0, P = 0.015; and 2.1, P = 0.0058, respectively) for WHO events. Conclusions: In HIV-infected Latin American children on stable HAART, 2 distinct VL thresholds (>2600 and >32,000 copies/mL) were identified for predicting children at significantly increased risk for HIV-related clinical illness, after accounting for CD4 level, hemoglobin level, and other significant factors.

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Phytochemical studies of Hortia brasiliana and Hortia oreadica (Rutaceae) have led to the identification of three novel dihydrocinnamic acids: 5-methoxy-2,2-dimethyl-2H-1-benzopyran-8-propanoic acid, 5,6-dimethoxy-2,2-dimethyl-2H-1-benzopyran-8-propanoic acid and erythro-2-hydroxy-4-methoxy-3-(1,2,3-trihydroxy-3-methylbutyl) benzenepropanoic acid from H. brasiliana and the second compound and six known dihydrocinnamic acids from H. oreadica. Engler included Hortia as the single Neotropical genus in the Toddalioideae subtribe Toddaliinae. However, the range of dihydrocinnamic acid derivatives found in H. brasiliana and H. oreadica show that they contain similar compounds to other species of Hortia and clearly point to their phytochemical affinities with other Rutoideae species. (C) 2012 Elsevier Ltd. All rights reserved.

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Abstract Background Prior to the selection of disinfectants for low, intermediate and high (sterilizing) levels, the decimal reduction time, D-value, for the most common and persistent bacteria identified at a health care facility should be determined. Methods The D-value was determined by inoculating 100 mL of disinfecting solution with 1 mL of a bacterial suspension (104 – 105 CFU/mL for vegetative and spore forms). At regular intervals, 1 mL aliquots of this mixture were transferred to 8 mL of growth media containing a neutralizing agent, and incubated at optimal conditions for the microorganism. Results The highest D-values for various bacteria were determined for the following solutions: (i) 0.1% sodium dichloroisocyanurate (pH 7.0) – E. coli and A. calcoaceticus (D = 5.9 min); (ii) sodium hypochlorite (pH 7.0) at 0.025% for B. stearothermophilus (D = 24 min), E. coli and E. cloacae (D = 7.5 min); at 0.05% for B. stearothermophilus (D = 9.4 min) and E. coli (D = 6.1 min) and 0.1% for B. stearothermophilus (D = 3.5 min) and B. subtilis (D = 3.2 min); (iii) 2.0% glutaraldehyde (pH 7.4) – B. stearothermophilus, B. subtilis (D = 25 min) and E. coli (D = 7.1 min); (iv) 0.5% formaldehyde (pH 6.5) – B. subtilis (D = 11.8 min), B. stearothermophilus (D = 10.9 min) and A. calcoaceticus (D = 5.2 min); (v) 2.0% chlorhexidine (pH 6.2) – B. stearothermophilus (D = 9.1 min), and at 0.4% for E. cloacae (D = 8.3 min); (vi) 1.0% Minncare® (peracetic acid and hydrogen peroxide, pH 2.3) – B. stearothermophilus (D = 9.1 min) and E. coli (D = 6.7 min). Conclusions The suspension studies were an indication of the disinfectant efficacy on a surface. The data in this study reflect the formulations used and may vary from product to product. The expected effectiveness from the studied formulations showed that the tested agents can be recommended for surface disinfection as stated in present guidelines and emphasizes the importance and need to develop routine and novel programs to evaluate product utility.

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At the present celiac disease has no known cure, and its only treatment is a strict lifelong adherence to a gluten-free diet. Cheese bread is a traditional Brazilian product and a safe option for celiacs. However, like other gluten-free breads, it has inherent low levels of fibers and minerals. The objective of this study was to evaluate the effect of incorporation of whole amaranth flour on the physical properties and nutritional value of cheese bread. Amaranth flour was incorporated at 10, 15, and 20% proportions in different formulations. The increasing amaranth levels darkened the product, reduced specific volume, and increased compression force. Ten percent amaranth-content cheese breads exhibited slight differences in physical properties compared with the controls. These results demonstrated the possibility of incorporating 10% of whole amaranth flour in the formulation of cheese bread resulting in a product with higher dietary fiber and iron contents and the same level of acceptance as that of the conventional formulation. The aim of this approach is to increase the availability of gluten-free bakery products with added nutritional value contributing to increase the variety of the diet of celiac patients.

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In this conference we report cross sections for elastic collisions of low-energy electrons with the HCOOH…(H2O)n complexes, with n = 1, 2 and 3. The scattering cross sections were computed with the Schwinger multichannel method [K. Takatsuka and V. McKoy, Phys. Rev. A 24 , 2473 (1981); Phys. Rev. A 30 , 1734 (1984)] with pseudopotentials [M. H. F. Bettega, L. G. Ferreira, and M. A. P. Lima, Phys. Rev. A 47, 1111 (1993)] in the static-exchange and static-exchange plus polarization approximations, for energies from 0.5 eV to 6 eV. We considered some diÆerent hydrogen-bonded structures for the complexes that were generated with classical Monte Carlo simulations [K. Coutinho and S. Canuto, J. Chem. Phys. 113, 9132, (2000)]. The aim of this work is to investigate the effect of the surrounding water molecules on the π* shape resonance of the solute. Previous theoretical and experimental studies carried out in the gas phase reported a π* state for HCOOH at around 1.9 eV. For the n = 1 case and for all complexes, the stabilization of the resonance was observed (it appears at lower energy compared to the value obtained in the gas phase), as reported previously for the CH2O…H2O complexes [T. C. Freitas, M. A. P. Lima, S. Canuto, and M. H. F. Bettega, Phys. Rev. A 80, 062710 (2009)]. This result indicates that the presence of the solvent may affect the processes related to the π* state, such as the molecular dissociation by electron impact. For the n = 2 case we have observed both stabilization and destabilization of the π* resonance, that is associated with the hydrogen bond donor or acceptor role of the water molecules in the complexes. For the n = 3 case, preliminary static-exchange results show the stabilization of the π* state. We propose an explanation of the stabilization/destabilization of the π* state in terms of the polarization of the solute due to the surrounding water molecules and the net charge in the solute.