30 resultados para Characteristics of texture
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo
Resumo:
Thermal treatment (thermal rectification) is a process in which technological properties of wood are modified using thermal energy, the result of Which is often value-added wood. Thermally treated wood takes on similar color shades to tropical woods and offers considerable resistance to destructive microorganisms and climate action, in addition to having high dimensional stability and low hygroscopicity. Wood samples of Eucalyptus grandis were subjected to various thermal treatments, as performed in presence (140 degrees C; 160 degrees C; 180 degrees C) or in absence of oxygen (160 degrees C; 180 degrees C; 200 degrees C) inside a thermal treatment chamber, and then studied as to their chemical characteristics. Increasing the maximum treatment temperatures led to a reduction in the holocellulose content of samples as a result of the degradation and volatilization of hemicelluloses, also leading to an increase in the relative lignin content. Except for glucose, all monosaccharide levels were found to decrease in samples after the thermal treatment at a maximum temperature of 200 degrees C. The thermal treatment above 160 degrees C led to increased levels of total extractives in the wood samples, probably ascribed to the emergence of low molecular weight substances as a result of thermal degradation. Overall, it was not possible to clearly determine the effect of presence or absence of oxygen in the air during thermal treatment on the chemical characteristics of the relevant wood samples.
Resumo:
We examine hemolymph ion regulation and the kinetic properties of a gill microsomal (Na+, K+)-ATPase from the intertidal hermit crab, Clibanarius vittatus, acclimated to 45 parts per thousand salinity for 10 days. Hemolymph osmolality is hypo-regulated (1102.5 +/- 22.1 mOsm kg(-1) H2O) at 45 parts per thousand but elevated compared to fresh-caught crabs (801.0 +/- 40.1 mOsm kg(-1) H2O). Hemolymph [Na+ (323.0 +/- 2.5 mmol L-1) and [Me2+) (34.6 +/- 1.0 mmol L-1) are hypo-regulated while [Ca2+] (22.5 +/- 0.7 mmol L-1) is hyper-regulated; [K+] is hyper-regulated in fresh-caught crabs (17.4 +/- 0.5 mmol L-1) but hypo-regulated (6.2 +/- 0.7 mmol L-1) at 45 parts per thousand. Protein expression patterns are altered in the 45 parts per thousand-acclimated crabs, although Western blot analyses reveal just a single immunoreactive band, suggesting a single (Na+, K+)-ATPase alpha-subunit isoform, distributed in different density membrane fractions. A high-affinity (Vm = 46.5 +/- 3.5 U mg(-1); K-0.5 = 7.07 +/- 0.01 mu mol L-1) and a low-affinity ATP binding site (Vm = 108.1 +/- 2.5 U mg(-1); K-0.5 = 0.11 +/- 0.3 mmol L-1), both obeying cooperative kinetics, were disclosed. Modulation of (Na+, K+)-ATPase activity by Mg2+, K+ and NH4+ also exhibits site-site interactions, but modulation by Na+ shows Michaelis-Menten kinetics. (Na+, K+)-ATPase activity is synergistically stimulated up to 45% by NH4+ plus K+. Enzyme catalytic efficiency for variable [K+] and fixed [NH4+] is 10-fold greater than for variable [NH4+] and fixed [K+]. Ouabain inhibited approximate to 80% of total ATPase activity (K-I=464.7 +/- 23.2 mu mol L-1), suggesting that ATPases other than (Na+, K+)-ATPase are present. While (Na+, K+)-ATPase activities are similar in fresh-caught (around 142 nmol Pi min(-1) mg(-1)) and 45 parts per thousand-acclimated crabs (around 154 nmol Pi min(-1) mg(-1)), ATP affinity decreases 110-fold and Na+ and K+ affinities increase 2-3-fold in 45 parts per thousand-acclimated crabs. (C) 2012 Elsevier Inc. All rights reserved.
Resumo:
CONTEXT AND OBJECTIVE: Injuries are an important cause of morbidity during adolescence, but can be avoided through learning about some of their characteristics. This study aimed to identify the most frequent injuries among adolescents attended at an emergency service. DESIGN AND SETTING: Retrospective descriptive study on adolescents attended at the emergency service of the Teaching Health Center, Faculdade de Medicina de Ribeirao Preto (FMRP), between January 1, 2009, and September 30, 2009. METHODS: Age, sex, type of injury, site, day and time of occurrence, part of body involved, care received, whether the adolescent was accompanied at the time of injury and whether any type of counseling regarding injury prevention had been given were analyzed. RESULTS: Among 180 adolescents attended, 106 (58.8%) were boys and 74 (41.1%) were girls. Their ages were: 10 to 12 (66/36.6%), 12 to 14 (60/33.3%) and 14 to 16 years (54/30%). The injuries had occurred in public places (47.7%) and at home (21.1%). The main types were bruises (45.1%) and falls (39.2%), involving upper limbs (46.1%), lower limbs (31%) and head/neck (13.1%). The injuries occurred in the afternoon (44.4%) and morning (30%), on Mondays (17.7%) and Thursdays (16.6%). Radiological examinations were performed on 53.8%. At the time of injury, 76.1% of the adolescents were accompanied. Some type of counseling about injury prevention had been received by 39.4%. CONCLUSIONS: Although the injuries were of low severity, preventive attitudes need to be incorporated in order to reduce the risks and provide greater safety for adolescents.
Resumo:
Purpose - The purpose of this paper is to develop an efficient numerical algorithm for the self-consistent solution of Schrodinger and Poisson equations in one-dimensional systems. The goal is to compute the charge-control and capacitance-voltage characteristics of quantum wire transistors. Design/methodology/approach - The paper presents a numerical formulation employing a non-uniform finite difference discretization scheme, in which the wavefunctions and electronic energy levels are obtained by solving the Schrodinger equation through the split-operator method while a relaxation method in the FTCS scheme ("Forward Time Centered Space") is used to solve the two-dimensional Poisson equation. Findings - The numerical model is validated by taking previously published results as a benchmark and then applying them to yield the charge-control characteristics and the capacitance-voltage relationship for a split-gate quantum wire device. Originality/value - The paper helps to fulfill the need for C-V models of quantum wire device. To do so, the authors implemented a straightforward calculation method for the two-dimensional electronic carrier density n(x,y). The formulation reduces the computational procedure to a much simpler problem, similar to the one-dimensional quantization case, significantly diminishing running time.
Resumo:
Objectives To estimate, by neonatal screening, the birth prevalence of congenital toxoplasmosis among live-born infants in Sergipe state, Brazil, and to investigate the clinical features of affected infants. Methods Dried blood spot specimens obtained from 15 204 neonates were assayed for the presence of anti-T. gondii IgM antibodies. Duplicate retesting was done in infants with positive and borderline results. Confirmatory testing in peripheral blood samples consisted of testing for anti-T. gondii IgG and IgM in infants and mothers. Those with possible congenital toxoplasmosis were evaluated and followed up to a median age of 20 months. Congenital infection was confirmed in the presence of persisting anti-T. gondii IgG antibodies beyond 12 months of age. All infants with confirmed infection were treated with pyrimethamine, sulfadiazine and folinic acid for 1 year. Results Fifty-three infants had detectable IgM in dried blood spot specimens. Confirmatory testing was reactive in 39/50, of which, 38 completed follow-up. Six of 15 204 newborns were diagnosed with congenital toxoplasmosis, resulting in an estimated birth prevalence of four per 10 000 [CI 95% 1.48.0]. Four infants (67%) showed signs of congenital toxoplasmosis in their first year of life; three (75%) had retinochoroidal scars, and one had cerebral calcifications. Two infants remained asymptomatic until 20 months of age. Conclusions The birth prevalence of congenital toxoplasmosis is high in the Brazilian state of Sergipe, with most of the infants showing ocular lesions. Preventive measures are strongly warranted.
Resumo:
A study was designed to characterize a carbapenem-resistant Klebsiella pneumoniae (KPSA01) isolated from a patient in Gauteng, South Africa without recent travel outside South Africa. Molecular characterization was done using isoelectric focusing, polymerase chain reaction and sequencing for bla(VIM), bla(IMP), bla(NDM), bla(CTX-Ms), bla(OXAs), bla(TEMs), and bla(SHV), plasmid-mediated quinolone resistance determinants, multilocus sequencing typing, plasmid replicon typing, and addiction factors. KPSA01 produced VIM-1 and belonged to the newly described sequence type ST569. The plasmid that harboured bla(VIM) typed within the narrow host range IncF replicon group, contained the aadA1 gene cassette, and tested positive for the vagCD and ccdAB addiction systems. This is the first report of VIM-1-producing K. pneumoniae outside Europe. It is important that surveillance studies be undertaken in Africa to determine if VIM-1-producing K. pneumoniae are present in significant numbers.
Resumo:
To estimate the prevalence of urinary incontinence (UI) in elderly individuals of low income assisted by the primary health care system in Sao Paulo, Brazil. In this community-based, observational, cross-sectional study, participants assisted by the health family program in Sao Paulo, Brazil, were sampled and interviewed face to face by questionnaire. Participants (n = 388) were selected from the collaborative program developed by the 10/66 Dementia Research Group, an International Network of investigators. Demographics, health history and a detailed assessment of UI and urinary symptoms were obtained. Prevalence of UI was calculated. Other variables included age, body mass index (BMI), duration of incontinence and characteristics of the symptoms. The association between UI and the variables was estimated using the Kruskal-Wallis test, Chi-squared test and Fisher test (depending on normality of the distribution and expected frequencies). Prevalence of UI was 38.4%. UI was more common in women than in men (50% vs. 18.3%, p < 0.001). Diabetes, obesity and hypertension were associated with UI. Almost 36.2% of the cases were of mixed incontinence, 26.8% of urge incontinence and 24.2% of stress incontinence. Men were more likely to have urge-incontinence, while women were more likely to have mixed incontinence (p = 0.001). UI is prevalent in the elderly of low income living in Sao Paulo and rates are higher than most previous studies. Chronic conditions such as hypertension, diabetes and obesity were associated with UI. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
Resumo:
The objective of this study was to investigate, in a population of crossbred cattle, the obtainment of the non-additive genetic effects for the characteristics weight at 205 and 390 days and scrotal circumference, and to evaluate the consideration of these effects in the prediction of breeding values of sires using different estimation methodologies. In method 1, the data were pre-adjusted for the non-additive effects obtained by least squares means method in a model that considered the direct additive, maternal and non-additive fixed genetic effects, the direct and total maternal heterozygosities, and epistasis. In method 2, the non-additive effects were considered covariates in genetic model. Genetic values for adjusted and non-adjusted data were predicted considering additive direct and maternal effects, and for weight at 205 days, also the permanent environmental effect, as random effects in the model. The breeding values of the categories of sires considered for the weight characteristic at 205 days were organized in files, in order to verify alterations in the magnitude of the predictions and ranking of animals in the two methods of correction data for the non-additives effects. The non-additive effects were not similar in magnitude and direction in the two estimation methods used, nor for the characteristics evaluated. Pearson and Spearman correlations between breeding values were higher than 0.94, and the use of different methods does not imply changes in the selection of animals.
Resumo:
Thiamethoxam is a systemic insecticide from the neonicotinoid group, nitroguanidin family which affects the nicotinic receptor acetyl choline in the insect membrane, wounding the nervous system and causing the death of the insect. It was used with success in the control of initial pests of several crops. It was considered that thiamethoxam has a bioactivator effect, because in the absence of insects promoted increase in vigor, development and productivity of crops. This work was carried out to verify if thiamethoxam causes histological changes in sugarcane roots. In this work, it was used optical microscopy, images arrest, tissue biometrics and statistical analysis, in young roots of sugarcane RB 83 5486 after the treatments with different thiamethoxam concentrations. It was determined changes in histological structure of tissues 7, 14, 21 and 28 days after the treatments, establishing its effects on root plant anatomy. It was verified that thiamethoxam increased root cortex width, increasing the vascular cylinder and the metaxylem vessel elements number in the vascular tissue until 21 days after application.
Resumo:
Listeria monocytogenes is a foodborne pathogen of great concern due to the high fatality rates of listeriosis. The consumption of RTE vegetables has increased in Brazil over the last two decades, but little is known about the risks associated to the consumption of these products. This study evaluated the prevalence and counts of L. monocytogenes in 512 packages of ready-to-eat vegetables marketed in Sao Paulo. The isolates were characterized for their serotypes, ribotypes, positivity for virulence genes inIA, inIC and inIJ, resistance to chlorine, growth rate variability and capability to form biofilm on stainless steel (AISI 304, #4) coupons. L. monocytogenes was detected in 3.1% of the samples. Only five samples presented countable levels, with counts between 1.0x10(1) and 2.6x10(2) CFU/g. Isolates belonged to serotypes 1/2b or 4b and most were positive for genes inIC and inIJ. Ribotypable isolates were grouped into four groups: 1038 (69.4%). 19175 (11.3%), 19191 (17.7%) and 18604 (one isolate). Most isolates survived to exposure to 125 ppm of a chlorine-based disinfectant for 3 min. All isolates were capable to attach to the coupons, reaching counts above 4 log(10) CFU/cm(2) and the growth rate (mu) at 25 degrees C of the majority of the isolates varied between 0.1 and 0.2 log OD/h, but for few strains the mu was as high as 0.26 log OD/h. Results of this survey indicate that RTE vegetables may be vehicles of L. monocytogenes strains with limited variation in serotype, ribotype and virulence factors but varying significantly in resistance to chlorine disinfectants, capability of forming biofilm and growth rate. Data obtained is of foremost importance to serve as baseline for the development of scientific-based policies to control the incidence of L. monocytogenes in RTE vegetables in Brazil. (c) 2012 Elsevier B.V. All rights reserved.
Resumo:
Purpose: To evaluate the dosimetric characteristics of a new formulation of MAGIC gel, called MAGIC-f, which contains the addition of 3.3% formaldehyde, resulting in a gel with increased thermal stability. Methods: MAGIC-f gel was prepared and stored in hermetically sealed plastic containers. After irradiation, magnetic resonance images (MRI) were acquired to evaluate dose and dose distribution. Dosimetric characterization was performed by means of depth dose measurements, dose response sensitivity and linearity, temporal stability, energy and dose rate dependence, dose integration using sequential beams, temperature influence during MRI acquisition and dose distribution integrity. Results: MAGIC-f depth dose measurements are compatible with the dosimetric table data within +/- 4% uncertainty. The dosimeter's R-2 response varies linearly with dose at least from 0 to 6 Gy. The time-course of the sensitivity of the dosimeter following irradiation, indicated stabilization after 2 weeks. The dosimeter's response to irradiation was altered by 6% when increasing the energy from cobalt beams to 10 MV beams. The dose rate dependence of this new formulation of gel dosimeter is small: less than 2.5% for a variation from 200 to 500 cGy/min, and the dependence with the fractionation scheme is about 50% smaller than for standard MAGIC gel, The dependence on scanning temperature was also verified, and the integrity of the dose distribution was confirmed for a period of 90 days. Conclusions: The results demonstrate the applicability of this new dosimeter in tridimensional dose distribution measurements. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
We describe production of methyl and ethyl esters derived from baru oil (Dipteryx alata Vog.). Water and alcohols are removed from the biodiesel obtained by simple distillation. We study the acidity, density, iodine number, viscosity, water content, peroxide number, external appearance, and saponification number of the oil, its methyl and ethyl esters (biodiesels) and their blends (B5, B10, B15, B20, and B30) with commercial diesel fuel.
Resumo:
Premise of the study: A set of eight microsatellite (simple sequence repeat [SSR]) markers for Lippia alba, an important medicinal and cosmetic plant, was developed to aid studies of genetic diversity and to define efficient strategies for breeding programs. Methods and Results: Using a (CT)(8)- and (GT)(8)-enriched library, a total of 11 SSR loci were developed and optimized in L. alba. Of the 11 loci, eight were found to be polymorphic after screening 61 accessions from two populations. The parameters used to characterize loci were expected heterozygosity (H-e) and number of alleles. A total of 44 alleles were identified, with an average of 5.5 alleles per loci, which were moderately to highly informative according to H-e. Conclusions: These new SSR markers have potential for informing genetic diversity, allele mining, and mapping studies and will be used to generate information for breeding programs of L. alba
Resumo:
This communication describes the general biochemical properties and some immunological characteristics of the venom from the Peruvian scorpion Hadruroides lunatus, which is the most medically relevant species in Peru. The soluble venom of this scorpion is toxic to mice, the LD50 determined was 0.1 mg/kg and 21.55 mg/kg when the venom was injected intracranial or intraperitoneally, respectively. The soluble venom displayed proteolytic, hyaluronidasic, phospholipasic and cardiotoxic activities. High performance liquid chromatography of the soluble venom resulted in the separation of 20 fractions. Two peptides with phospholipasic activity were isolated to homogeneity and their molecular masses determined by mass spectrometry (MALDI TOF). Anti-H. lunatus venom sera were produced in rabbits. Western blotting analysis showed that most of the protein content of this venom is immunogenic. H. lunatus anti-venom displayed consistent cross-reactivity with venom antigens from the new World-scorpions Tityus serrulatus and Centruroides sculpturatus venoms; however, a weaker reactivity was observed against the venom antigens from the old World-scorpion Androctonus australis Hector. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
The NNW-trending Nova Lacerda tholeiitic dike swarm in Mato Grosso State, Central Brazil, intrudes the Nova Lacerda granite (1.46 Ga) and the Jauru granite-greenstone terrain (ca. 1.79-1.77 Ga). The swarm comprises diabases I and II and amphibolites emplaced at ca. 1.38 Ga. Geochemical data indicate that these are evolved tholeiites characterized by high LILE/HSFE and LREE/HSFE ratios. Isotopic modelling yields positive epsilon(Nd)(T) values (+0.86 to +2.65), whereas values for epsilon(Sr)(T) range from positive to negative (+1.96 to -5.56). Crustal contamination did not play a significant petrogenetic role, as indicated by a comparison of isotopic data (Sr-Nd) from both dikes and country rocks, and by the relationship between isotopic and geochemical parameters (SiO2, K2O, Rb/Sr, and La/Yb) of the dikes. We attribute the origin of these tholeiites to fractional crystallization of evolved melts derived from a heterogeneous mantle source. Comparison of the geochemical and isotopic data of the studied swarm and other tholeiitic Mesoproterozoic mafic intrusions of the SWAmazonian Craton the Serra da Providencia, Colorado, and Nova Brasilandia bimodal suites - indicates that parental melts of the Nova Lacerda swarm were derived from the most enriched mantle source. This enrichment was probably caused by the stronger influence of the EMI component on the DMM end-member. These data, coupled with trace element bulk-rock geochemistry of the country rocks, and comparisons with the Colorado Complex of similar age, suggest a continental-margin arc setting for the emplacement of the Nova Lacerda dikes.