956 resultados para Stabilization of looking
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The use of animal models in biomedical research is ever increasing. Models that use primates might also have advantages in terms of low maintenance costs and availability of biological knowledge, thereby favoring their use in different experimental protocols. Many current stress studies use animal models at different developmental stages since biological response differs during ontogeny. The aims of this study were to perform a detailed characterization of the developmental stages of common marmosets (Callithrix jacchus), a very important animal model used in biomedical research. Ten subjects, 6 females and 4 males, were followed from birth to initial adult age (16 months). Behavioral and fecal collection for measurement of adrenal (cortisol) and sex (progesterone, estradiol and androgens) hormones took place twice a week during the first month of life and once a week for the remainder of the study. Behavior was observed for 30 minutes in the morning (0700-09:00h) and afternoon (12:00-14:00h). Behavioral profile showed changes during ontogeny, characterizing the 4 developmental stages and the respective phases proposed by Leão et al (2009).. Differentiation of developmental stages was considered using the onset, end, change and stabilization of the behavioral profile parental care (weaning and carrying), ingestion (solid food), affiliation (social grooming) and autogrooming, agonism (scent marking and piloerection) and play behavior and endocrine profile. Infant weaning and carrying terminated within the infantile stage and the peak of solid food ingestion was recorded in the infantile III phase. Receiving grooming was recorded earlier than grooming performed by the infant and autogrooming. The first episode of scent marking was recorded in the 4th week and it was the least variable behavior, in terms of its onset, which, in almost all animals, was between the 5th and 7th week of life. Solitary play and play with the twin started around the 7th week and play with other members of the group started 8 weeks later. Sex hormone secretion started to differ from basal levels between the 21st and 23rd week of life, in males and females, suggesting that puberty occurs simultaneously in both sexes. Basal cortisol, even at an early age, was higher in females than in males. However, cortisol was not correlated with the juvenile stage, as expected, since this stage corresponds to the transition between infancy and adult age and most behaviors are intensified by this time. The behavioral and endocrine profile of subadult animals did not differ from that of the adults. These results provide more detailed parameters for the developmental process of C. jacchus and open new perspectives for the use of experimental approaches focused on the intermediate ontogenetic phases of this species
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Were synthesized systems Ni0,5Zn0,5Fe2O4, i0,2Zn0,5Mn0,3Fe2O4, Mn0,5Zn0,5Fe2O4, Ni0,5Mg0,5Fe2O4, Ni0,2Cu0,3Zn0,5Fe2O4 and Ni0,2Cu0,3Zn0,5Mg0,08Fe2O4, the precursors citrate method. The decomposition of the precursors was studied by thermogravimetric analysis and spectroscopy in the infrared region, the temperature of 350°C/3h. The evolution of the phases formed after calcinations at 350, 500, 900 and 1100ºC/3h was accompanied by X-ray diffraction using the Rietveld refinement to better identify the structures formed. The materials were also analyzed by scanning electron microscopy, magnetic measurements and analysis of the reflectivity of the material. The samples calcined at different temperatures showed an increase of crystallinity with increasing calcination temperature, verifying that for some compositions at temperatures above 500°C precipitates of second phase such as hematite and CuO. The compositions of manganese present in the structure diffusion processes slower due to the ionic radius of manganese is greater than for other ions substitutes, a fact that delays the stabilization of spinel structure and promotes the precipitation of second phase. The compositions presented with copper precipitation CuO phase at a temperature of 900 and 1100ºC/3h This occurs according to the literature because the concentration of copper in the structure is greater than 0.25 mol%. The magnetic measurements revealed features of a soft ferrimagnetic material, resulting in better magnetic properties for the NiZn ferrite and NiCuZnMg at high temperatures. The reflectivity measurements showed greater absorption of electromagnetic radiation in the microwave band for the samples calcined at 1100ºC/3h, which has higher crystallite size and consequently the formation of multi-domain, increasing the magnetization of the material. The results of absorption agreed with the magnetic measurements, indicating among the ferrites studied, those of NiZn and NiCuZnMg as better absorbing the incident radiation.
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In this study five compositions were synthesized zirconia doped with cerium and neodymium ions in the system Ce10-xNdx Zr90O2 with 0,5 ≤ x ≤ 4,0 using the Pechini method. The powders were characterized by thermogravimetric analysis, differential thermal analysis, infrared spectroscopy and X-ray diffraction, with application of Rietveld refinement of the calcination temperatures of 350ºC/3h and 30 minutes at 900ºC/3h. All compositions stabilized with a mixture of cubic and tetragonal phase zirconia. The samples were pressed into bars and sintered at 1500°C/3h and 1500°C/6h, being characterized by Xray diffraction, with application of the Rietveld refinement, density and porosity using Archimedes method, scanning electron microscopy and resistance the three point bending. It has been observed the increase in strength with increasing sintering temperature for the compositions x = 2,0 and x = 4,0. For x = 2,0 the main phase was the cubic with 92,56% with crystallite size of 0,56 μm, density and porosity of 96,82% from 1,36%. For x = 4,0 was a mixture of cubic and tetragonal phase with 21% and 37,98%, respectively. The crystallite size was 54,21 nm and 49,64 nm with a density porosity of 97,45% and 1,32% respectively. In the analysis of the fracture surface was observed a greater amount of grain fracture intragranular type, which contribute to increase the mechanical strength of the ceramic. Increased addition of the neodymium ion in the crystal lattice of the zirconium showed a nearly linear behavior with increasing mechanical strength of the zirconia ceramic. Was obtained a bending resistance of 537 ± 38 MPa for the composition x = 2,0 predominantly attributed to cubic phase with 92,56%
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OBJETIVO: Avaliar a eficiência do clampe de Ganz na estabilização e redução dos deslocamentos da pelve, quando utilizado no tratamento de urgência, além de aquilatar eventuais dificuldades e facilidades do método. MÉTODOS: O clampe de Ganz foi utilizado no tratamento de urgência em 31 pacientes com graves lesões do anel pélvico (Tile C) associadas a importante instabilidade hemodinâmica. RESULTADO: Entre os pacientes, 27 (87,1%) apresentaram evolução favorável, com estabilização, redução dos deslocamentos e compressão da região posterior do anel, além de estabilização hemodinâmica, e quatro (12,9%) evoluíram para óbito. CONCLUSÃO: O clampe de Ganz mostrou-se eficiente ferramenta no tratamento de urgência das lesões do anel pélvico, por ser de concepção simples, de rápida colocação, não impedir ou dificultar procedimentos no abdome e, principalmente, por permitir a estabilização da pelve, redução dos deslocamentos e compressão na região posterior do anel, local onde ocorrem os maiores sangramentos, reduzindo-os ou eliminando-os.
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Two birds were presented with malunion fractures. The first was a young toco toucan (Ramphastos toco) with malunion of the tarsometatarsus that was treated by an opening-corrective osteotomy and an acrylic-pin external skeletal fixator (type II) to stabilize the osteotomy. The second bird was m adult southern caracara (Caracara plancus) with radial and ulnar malunion that was treated by closing-wedge osteotomies. Stabilization of the osteotomy sites was accomplished through 1 bone plate fixed cranially on the ulna with 6 cortical screws and an interfragmentary single wire in radius. In both cases, the malunion was corrected, but the manus of the southern caracara was amputated because of carpal joint luxation that induced malposition of the feathers.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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We show that in an SU(2)circle timesU(1) model with a Dine-Fischler-Srednicki-like invisible axion it is possible to obtain (i) the convergence of the three gauge coupling constants at an energy scale near the Peccei-Quinn scale; (ii) the correct value for sin(2)theta<^>(W)(M-Z); (iii) the stabilization of the proton by the cyclic Z(13)circle timesZ(3) symmetries which also stabilize the axion as a solution to the strong CP problem. Concerning the convergence of the three coupling constants and the prediction of the weak mixing angle at the Z peak, this model is as good as the minimal supersymmetric standard model with mu(SUSY)=M-Z. We also consider the standard model with six and seven Higgs doublets. The main calculations were done in the 1-loop approximation but we briefly consider the 2-loop contributions.
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We study the macroscopic quantum tunneling, self-trapping phenomena in two weakly coupled Bose-Einstein condensates with periodically time-varying atomic scattering length.The resonances in the oscillations of the atomic populations are investigated. We consider oscillations in the cases of macroscopic quantum tunneling and the self-trapping regimes. The existence of chaotic oscillations in the relative atomic population due to overlaps between nonlinear resonances is showed. We derive the whisker-type map for the problem and obtain the estimate for the critical amplitude of modulations leading to chaos. The diffusion coefficient for motion in the stochastic layer near separatrix is calculated. The analysis of the oscillations in the rapidly varying case shows the possibility of stabilization of the unstable pi-mode regime. (C) 2000 Published by Elsevier B.V. B.V. PACS: 03.75.Fi; 05.30.Jp.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Skeletal muscle fibers areas, the weight of body, carcass and muscle, the gastric content and the length of intestines and caecum of Norfolk rabbit from neonate to 26th week were measured. Types of fibers and areas were studied in -70-degrees-C frozen blocks of flexor carpo radialis muscle. Some sections were stained with Haematoxylin and Eosin and others were submitted to SDH, NADH-TR and m-ATPase, followed by acid and alkali preincubations. All parameters revealed a high degree of correlation. Carcass weight/body weight ratio reached 55,1% at 10th week. From neonate to 26th week, the areas of SO, FOG and FG muscle fibers increased of x9.1, x12.4 and x22.2. While SO and FOG fibers tend to stabilize their growth at 10th week, FG fibers were active at this age. Due to early stabilization of SO and FOG fibers growth, the additional increase in muscle tissue in attributed mainly to hypertrophy of FG fibers.
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The new complex [Cu(NCS)(2)(pn)] (1) (pn = 1,3-propanediamine) has been synthesized and characterized by elemental analysis, infrared and electronic spectroscopy. Single crystal X-ray diffraction studies revealed that complex 1 is made up of neutral [Cu(NCS)(2)(pn)] units which are connected by mu-1,3,3-thiocyanato groups to yield a 2D metal-organic framework with a brick-wall network topology. Intermolecular hydrogen bonds of the type NH...SCN and NH...NCS are also responsible for the stabilization of the crystal structure. (c) 2007 Elsevier B.V. All rights reserved.
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The present work was conducted with the initial purpose of looking for the characterization of Azospirillum brasilense strain ATCC 29.145 mutants induced by insertions of the transposon Tn-5. The strategy used to transfer such mobile element was based on the vector named pJB4JI