972 resultados para modified local ternary pattern
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Guignardia citricarpa, the causal agent of citrus black spot, forms airborne ascospores on decomposing citrus leaves and water-spread conidia on fruits, leaves and twigs. The spatial pattern of diseased fruit in citrus tree canopies was used to assess the importance of ascospores and conidia in citrus black spot epidemics in Sao Paulo State, Brazil. The aggregation of diseased fruit in the citrus tree canopy was quantified by the binomial dispersion index (D) and the binary form of Taylor`s Power Law for 303 trees in six groves. D was significantly greater than 1 in 251 trees. The intercept of the regression line of Taylor`s Power Law was significantly greater than 0 and the slope was not different from 1, implying that diseased fruit was aggregated in the canopy independent of disease incidence. Disease incidence (p) and severity (S) were assessed in 2875 citrus trees. The incidence-severity relationship was described (R-2 = 88.7%) by the model ln(S) = ln(a) + bCLL(p) where CLL = complementary log-log transformation. The high severity at low incidence observed in many cases is also indicative of low distance spread of G. citricarpa spores. For the same level of disease incidence, some trees had most of the diseased fruit with many lesions and high disease severity, whereas other trees had most of the fruit with few lesions and low disease severity. Aggregation of diseased fruit in the trees suggests that splash-dispersed conidia have an important role in increasing the disease in citrus trees in Brazil.
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Maize (Zea mays L.) is a very important cereal to world-wide economy which is also true for Brazil, particularly in the South region. Grain yield and plant height have been chosen as important criteria by breeders and farmers from Santa Catarina State (SC), Brazil. The objective of this work was to estimate genetic-statistic parameters associated with genetic gain for grain yield and plant height, in the first cycle of convergent-divergent half-sib selection in a maize population (MPA1) cultivated by farmers within the municipality of Anchieta (SC). Three experiments were carried out in different small farms at Anchieta using low external agronomic inputs; each experiment represented independent samples of half-sib families, which were evaluated in randomized complete blocks with three replications per location. Significant differences among half-sib families were observed for both variables in all experiments. The expected responses to truncated selection of the 25% better families in each experiment were 5.1, 5.8 and 5.2% for reducing plant height and 3.9, 5.7 and 5.0% for increasing grain yield, respectively. The magnitudes of genetic-statistic parameters estimated evidenced that the composite population MPA1 exhibits enough genetic variability to be used in cyclical process of recurrent selection. There were evidences that the genetic structure of the base population MPA1, as indicated by its genetic variability, may lead to expressive changes in the traits under selection, even under low selection pressure.
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Background: Dentists of Lar Sao Francisco observed during dental treatment that children with cerebral palsy (CP) had increased heart rate (HR) and lower production of saliva. Despite the high prevalence of CP found in the literature (2.08-3.6/1000 individuals), little is known about the electrocardiographic (ECG) characteristics, especially HR, of individuals with CP. Objective: This study aimed to investigate the hypothesis that individuals with CP have a higher HR and to define other ECG characteristics of this population. Methods: Ninety children with CP underwent clinical examination and 12-lead rest ECG. Electrocardiographic data on rhythm, HR, PR interval, QRS duration, P/QRS/T axis, and QT, QTc and T(peak-end) intervals (minimum, mean, maximum, and dispersion) were measured and analyzed then compared with data from a control group with 35 normal children. Fisher and Mann-Whitney U tests were used, respectively, to compare categorical and continuous data. Results: Groups cerebral palsy and control did not significantly differ in age (9 +/- 3 x 9 +/- 4 years) and male gender (65% x 49%). Children with CP had a higher HR (104.0 +/- 20.6 x 84.2 +/- 13.3 beats per minute; P < .0001), shorter PR interval (128.8 +/- 15.0 x 138.1 +/- 15.1 milliseconds; P = .0018), shorter QRS duration (77.4 +/- 8.6 x 82.0 +/- 8.7 milliseconds; P = .0180), QRS axis (46.0 degrees +/- 26.3 degrees x 59.7 degrees +/- 24.8 degrees; P = .0024) and T-wave axis (34.3 degrees +/- 28.9 degrees x 42.9 degrees +/- 17.1 degrees; P = .034) more horizontally positioned, and greater mean QTc (418.1 +/- 18.4 x 408.5 +/- 19.4 milliseconds; P = .0110). All the electrocardiogram variables were within the reference range for the age group including those with significant differences. Conclusion: Children with CP showed increased HR and other abnormal ECG findings in the setting of this investigation. Further studies are needed to explain our findings and to correlate the increased HR with situations such as dehydration, stress, and autonomic nervous disorders. (C) 2011 Elsevier Inc. All rights reserved.
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The objective of this study was to evaluate the effect of particle size and concentration of poly(F.-caprolactone) and adipate modified starch blend on mineralization in soils with differing textures, comparing it with polyethylene under the same experimental conditions. Two soil types were used: a Kandiudalfic Eutrudox with a clayey texture and an Arenic Hapludult with a sandy texture. The two different plastic specimens were incorporated in the form of plastic films with three increasing particle sizes and six doses, from 0 to 2.5 mg C g(-1) soil. Each plastic dose was incorporated into 200 g of soil placed in a hermetically closed jar at 28 degrees C, and incubated for a 120-day period to determine CO(2) evolution. Once again it was confirmed that polyethylene is almost non-biodegradable, in contrast to PCL/S, which can be defined as a biodegradable material. Soil texture affected the mineralization kinetics of the plastic specimens, with higher values for the clayey soil. No changes in soil microbial biomass-C or -N were observed by adding polyethylene and PCL/S to the soil. Also, no significant differences were observed on seed emergence and development of rice seedlings (Oryza sativa L.) in plastic modified soil. (C) 2009 Elsevier Ltd. All rights reserved.
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We introduce the log-beta Weibull regression model based on the beta Weibull distribution (Famoye et al., 2005; Lee et al., 2007). We derive expansions for the moment generating function which do not depend on complicated functions. The new regression model represents a parametric family of models that includes as sub-models several widely known regression models that can be applied to censored survival data. We employ a frequentist analysis, a jackknife estimator, and a parametric bootstrap for the parameters of the proposed model. We derive the appropriate matrices for assessing local influences on the parameter estimates under different perturbation schemes and present some ways to assess global influences. Further, for different parameter settings, sample sizes, and censoring percentages, several simulations are performed. In addition, the empirical distribution of some modified residuals are displayed and compared with the standard normal distribution. These studies suggest that the residual analysis usually performed in normal linear regression models can be extended to a modified deviance residual in the proposed regression model applied to censored data. We define martingale and deviance residuals to evaluate the model assumptions. The extended regression model is very useful for the analysis of real data and could give more realistic fits than other special regression models.
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Gene duplication followed by acquisition of specific targeting information and dual targeting were evolutionary strategies enabling organelles to cope with overlapping functions. We examined the evolutionary trend of dual-targeted single-gene products in Arabidopsis and rice genomes. The number of paralogous proteins encoded by gene families and the dual-targeted orthologous proteins were analysed. The number of dual-targeted proteins and the corresponding gene-family sizes were similar in Arabidopsis and rice irrespective of genome sizes. We show that dual targeting of methionine aminopeptidase, monodehydroascorbate reductase, glutamyl-tRNA synthetase, and tyrosyl-tRNA synthetase was maintained despite occurrence of whole-genome duplications in Arabidopsis and rice as well as a polyploidization followed by a diploidization event (gene loss) in the latter.
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The storage of Carioca bean at 30 C and 75% relative humidity for eight months altered the solubilization pattern of hulls non-starch polysaccharides The polysaccharide physicochemical pattern changed resulting in a shift in the composition of water-soluble and water-insoluble polysaccharides caused by the insolubilization of galacturonans and xyloglucan Hulls make up 10% of whole beans which showed an increase of about 5% in water-insoluble polysaccharides and a decrease of about 1% in water-soluble polysaccharides with aging These values suggest that cotyledons and hulls together account for an increase of about 2 g of water-insoluble polysaccharides and a decrease of 1 5 g of water-soluble polysaccharides per 100 g of beans This change in the polysaccharide composition may produce a considerable difference in the dietary fiber profile The alterations observed in bean hull non-starch polysaccharide composition were similar to those previously observed in the cotyledon (C) 2010 Elsevier Ltd All rights reserved
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Chromoblastomycosis is a chronic skin infection caused by the fungus Fonsecaea pedrosoi. Exploring the reasons underlying the chronic nature of F. pedrosoi infection in a murine model of chromoblastomycosis, we find that chronicity develops due to a lack of pattern recognition receptor (PRR) costimulation. F. pedrosoi was recognized primarily by C-type lectin receptors (CLRs), but not by Toll-like receptors (TLRs), which resulted in the defective induction of proinflammatory cytokines. Inflammatory responses to F. pedrosoi could be reinstated by TLR costimulation, but also required the CLR Mincle and signaling via the Syk/CARD9 pathway. Importantly, exogenously administering TLR ligands helped clear F. pedrosoi infection in vivo. These results demonstrate how a failure in innate recognition can result in chronic infection, highlight the importance of coordinated PRR signaling, and provide proof of the principle that exogenously applied PRR agonists can be used therapeutically.
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The purpose of this study was to attain and characterize ternary complexes of simvastatin, beta-cyclodextrin (beta CD) and different polymers, and then select those that lead to a greater increase in drug solubility. The complexes were prepared with the co-evaporation method and the polymers used were polyethylene glycol 1500, polyethylene glycol 4000, povidone, copovidone, crospovidone, maltodextrin and hydroxypropyl methyl cellulose. The characterization of complexes was carried out through aqueous solubility, DSC and TG. There was an increase in solubility for all the complexes prepared with beta CD and the different polymers, but only when crospovidone and maltodextrin were used was there a significant difference observed between the solubility of the physical mixture and that of the complex. The DSC curves indicate that the non-complexed drug is even in the sample of the complex with higher solubility, thus none of the polymers was able to achieve a total complexation of the drug.
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The aim of this study was to determine whether inclusion complexes between 2-hydroxypropyl-beta-cyclodextrin (HP beta CD) and finasteride (FIN) are formed, and to characterize these. Equimolar FIN/HP beta CD solid systems in the presence or absence of 0.1% (w/v) of polyvinylpyrrolidone K30 (PVP K30) or 0.3% of chitosan were prepared by coevaporation and freeze-drying methods. The systems were characterized by phase solubility, NMR, DSC, and XRD analysis. The results suggest that true binary and ternary inclusion complexes were formed. (c) 2009 Elsevier Ltd. All rights reserved.
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Grafts of biological tissues have been used since the 1960s as an alternative to the mechanical heart prostheses. Nowadays, the most consolidated treatment to bovine pericardial (BP) bioprostheses is the crosslinking with glutaraldehyde (GA), although GA may induce calcification in vivo. In previous work, our group demonstrated that electron beam irradiation applied to lyophilized BP in the absence of oxygen promoted crosslinks among collagen fibers of BP tissue. In this work, the incorporation of silk fibroin (SF) and chitosan (CHIT) in the BP not treated with GA was studied. The samples were irradiated and then analyzed for their cytotoxicity and the ability of adhesion and growth of endothelial cells. Initially, all samples showed cytotoxicity. However, after a few washing cycles, the cytotoxicity due to acetic acid and ethanol residues was removed from the biomaterial making it suitable for the biofunctional test. The samples modified with SF/CHIT and electron beam irradiated favored the adhesion and growth of endothelial cells throughout the tissue.
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PEGylation is a strategy that has been used to improve the biochemical properties of proteins and their physical and thermal stabilities. In this study, hen egg-white lysozyme (EC 3.2.1.17; LZ) was modified with methoxypolyethylene glycol-p-nitrophenyl carbonate (mPEG-pNP, MW 5000). This PEGylation of LZ produced conjugates that retained full enzyme activity with glycol chitosan, independent of degree of enzyme modification; its biological activity with the substrate Micrococcus lysodeikticus was altered according to its degree of modification. The conjugate obtained with a low degree of mPEG-pNP/NH(2) modification was studied by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), demonstrating a spectral peak at m/z 19,988 Da with 77% of its original enzymatic activity. Spectroscopic studies of Fourier transform infrared (FIR) and circular dichroism (CD) did not show any relevant differences in protein structure between the native and conjugate LZ. Studies of the effects of pH and temperature on PEGylated LZ indicated that the conjugate was active over a broad pH range, stable at 50 degrees C, and demonstrated resistance to proteolytic degradation. (C) 2010 Elsevier B.V. All rights reserved.
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PEGylation is one of the most promising and extensively studied strategies for improving the pharmacological properties of proteins as well as their physical and thermal stability. Purified lysozyme obtained from hen egg white by batch mode was modified by PEGylation with methoxypolyethyleneglycol succinimidyl succinato (mPEG-SS, MW 5000). The conjugates produced retained full enzyme activity with the substrate glycol chitosan, independent of degree of enzyme modification, although lysozyme activity with the substrate Micrococcus lysodeikticus was altered according to the degree of modification. The conjugate with a low degree of modification by mPEG-SS retained 67% of its enzyme activity with the M. lysodeikticus substrate. The mPEG-SS was also shown to be a highly reactive polymer. The effects of pH and temperature on PEGylated lysozymes indicated that the conjugate was active over a wide pH range and was stable up to 50 degrees C. This conjugate also showed resistance to proteolytic degradation, remained stable in human serum, and displayed greater antimicrobial activity than native lysozyme against Gram-negative bacteria.
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This article reports on modified chitosan as an alternative substance for protecting loss of volatile compounds during freeze drying. Moisture sorption isotherms of freeze-dried D-limonene emulsions in modified chitosan were determined at 15, 25, and 35 degrees C. The data were adjusted to the GAB model. Maltodextrin was used in a parallel experiment. Flavor released from microcapsules was measured. The monolayer humidity, the sorption heat, the diffusivity coefficients, and the surface area of freeze-dried D-limonene emulsions were determined.
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Feijo, T.S., Cardozo, SX, Daleprane, J.B., Sabaa Srur, A.U.O. & Boaventura, G.T. [Evaluation of the influence of the proteinic quality of the genetically modified and organic soy beans in the growth of two generations of rats Wistar.] Avaliacao da influencia da qualidade proteica da soja geneticamente modificada e organica no crescimento de duas geracoes de ratos Wistar. Revista Brasileira de Medicina Veterinaria, 31(3):139-144, 2009. Programa de Pos-Graduacao em Patologia, Hospital Universitario Antonio Pedro. Centro de Ciencias Medicas, Universidade Federal Fluminense. Rua Marques do Parana, 303, Niteroi, RJ 24030-210, Brasil. E-mail: sergian@ufnj.br Sixty four Wistar rats, male of two consecutive generations determined as F(0) and F(1) were used to study the cumulative effect of two variety soy beans, cultivated with organic seasoning and genetically modified, The animals of each generation were divided into three groups of eight rats each fed on diets consisted of organic soy, soy genetically modified and casein respectively. All the animals received water and the diet ad libitum for period of 28 days. Where the diet consumption and the animals weight were evaluated. After statistic analysis of the results no expressive differences were observed on diet consumption, weight variation, protein efficient ratio and food efficiency ratio on same group of animals in the different generations. On the other hand, significant difference was found on final proteinic retention on animal descendants of the same groups; however of different generations. With this, the supplementation of organic soy with L-cistin provided better avail of this protein in relation to the protein of the soy genetically modified. However, this supplementation did not reveal efficiency in keeping the proteinic employment from one generation to another one, since soy varieties presented better performance on F(0) generation when compared with F(1).