Quantitative characterization of multi-phase materials by digital image processing

An automatic image processing and analysis technique has been developed for quantitative characterization of multi-phase materials. For the development of this technique is used the Khoros system that offers the basic morphological tools and a flexible, visual programming language. These techniques are implemented in a highly user oriented image processing environment that allows the user to adapt each step of the processing to his special requirements.To illustrate the implementation and performance of this technique, images of two different materials are processed for microstructure characterization. The result is presented through the determination of volume fraction of the different phases or precipitates.

Alternative Model of Three-Phase Transmission Line Theory-Based Modal Decomposition

In this paper is shown the development of a transmission line, based on discrete circuit elements that provide responses directly in the time domain and phase. This model is valid for ideally transposed rows represent the phases of each of the small line segments are separated in their modes of propagation and the voltage and current are calculated at the modal field. However, the conversion phase-mode-phase is inserted in the state equations which describe the currents and voltages along the line of which there is no need to know the user of the model representation of the theory in the field lines modal.

Monoclinic-tetragonal phase transition in Pb(Zr1-xTix)O-3 studied by infrared spectroscopy

The discovery of a new monoclinic phase in the PbZr1-xTixO3 (PZT) system in the vicinity of the morphotropic phase boundary (MPB), previously considered as a region where the rhombohedral and tetragonal phases of PZT coexist, was recently reported. Investigations of this new phase were reported using different techniques such as high-resolution synchrotron x-ray powder diffraction and Raman spectroscopy. The main objective has been to define a new phase diagram of PZT. In this context, infrared spectroscopic studies were performed in the vicinity of the MPB and studies were initially centred on a PZT sample with x = 0.49 mol% Ti content. Results suggested that the monoclinic --> tetragonal phase transition occurs at 237 K, confirming the use of IR as a useful technique to investigate this phase transition.

Evidence of distinct phase transformations in lithium phosphate glass Li2O-P2O5

The purpose of this work is to study the Li2O-P2O5 glass using the differential scanning calorimetry (DSC) and x-ray diffraction (XRD) techniques to understand the crystallization process in this glass matrix. To study the glass by DSC, screened samples with different particle sizes to resolve the crystallization peaks were used. Both crystallization peaks were attributed to Li6P6O18 and LiPO3 phases. This evidence was corroborated by XRD analysis on glasses annealed at different temperatures in order to crystallize these phases.

Organ tropism during the acute and chronic phases of Trypanosoma cruzi infection in BALB/c mice

The aim of the present study was to investigate the presence of Trypanosoma cruzi in the heart, liver, lung, and kidneys, using hemoculture and PCR analysis, of mice infected with different parasite strains during the acute and chronic phases of infection. Parasitemia curves revealed strain-specific biological behaviors. For the Y and JLP strains, the acute phase of infection started at days six and ten post-infection, parasitemia peaked at days seven and 15 post-infection, the chronic phase started at days nine and 28 post-infection, and animals started dying at days 19 and 120 post-infection, respectively. When the two strains were compared, the JLP strain exhibited reduced and slower replication rates associated with a delayed peak of parasitism and reduced parasite burdens. However, parasites were detected in all studied organs using PCR analysis. The capacity of both strains to infect different organs likely influences disease pathogenesis.

Morphologic and quantitative evaluation of preantral follicles of buffalo (Bubalus bubalis) in different reproductive phases

The objectives of the present study were to estimate the population of the normal and degenerated preantral follicles of buffaloes in different reproductive phases and to classify the different types of degeneration of ovarian preantral follicles. For this, 18 ovaries were divided in three groups: prepubertal, non pregnat and pregnant adult females. The ovaries were collected from a slaughterhouse (Frigol - Brazil) and processed for classic histological examination. The follicular population was estimated according to Cahill et al. (1979) and calculated according to Gougeon & Chainy (1987). Young buffaloes, pregnant and non pregnat adults presented an average number of 15.5, 3.7 and 8.9 preantral follicles with normal morphology and type I (the degeneration was observed just in oocyte) and II (oocyte and granulosa cells were degenerated) degeneration, respectively. This experiment demonstrated that the proportions of primordial, primary and secondary follicles were affected by reproductive phase. A significant difference was observed considering the proportions of preantral follicles with normal morphology and Type I degeneration in all reproductive phases evaluated. The primary follicles presented more percentage of Type I degeneration that the others follicles and the primordial and primary follicles presented more percentage of Type II degeneration in three reproductive phases evaluated.

Differential MMP-2 and MMP-9 Activity and Collagen Distribution in Skeletal Muscle from pacu (Piaractus mesopotamicus) During Juvenile and Adult Growth Phases

Here, we evaluated collagen distribution and matrix metalloproteinases (MMPs) MMP-2 and MMP-9 activities in skeletal muscle of pacu (Piaractus mesopotamicus) during juvenile and adult growth phases. Muscle samples from juvenile and adult fishes were processed by histochemistry for collagen system fibers and for gelatin-zymography for MMP-2 and MMP-9 activities analysis. Picrosirius staining revealed a myosept, endomysium, and perimysium-like structures in both growth phases and muscle types, with increased areas of collagen fibers in adults, mainly in red muscle. Reticulin staining showed that reticular fibers in the endomysium-like structure were thinner and discontinuous in the red muscle fibers. The zymography revealed clear bands of the pro-MMP-9, active-MMP-9, intermediate-MMP-2, and active-MMP-2 forms in red and white muscle in both growth phases. MMP-2 activity was more intense in juvenile than adult muscle fibers. Comparing the red and white muscle types, MMP-2 activity was significantly higher in red muscle in adult phase only. The activity of MMP-9 forms was similar in juvenile red and white muscles and in the adult red muscle, without any activity in adult white muscle. In conclusion, our results show that, in pacu, the higher activities of MMP-2 and -9 are associated with the rapid muscle growth in juvenile age and in adult fish, these activities are related with a different red and white muscle physiology. This study may contribute to the understanding muscle growth mechanisms and may also contribute to analyse red and the white muscle parameters of firmness and softness, respectively, of the commercial product. Anat Rec, 292:387-395, 2009. (C) 2009 Wiley-Liss, Inc.

Differential expression of myogenic regulatory factor MyoD in pacu skeletal muscle (Piaractus mesopotamicus Holmberg 1887: Serrasalminae, Characidae, Teleostei) during juvenile and adult growth phases

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Imbibition phases and germination response of Mimosa bimucronata (Fabaceae: Mimosoideae) to water submersion

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Performance comparisons of the kicking of stationary and rolling balls in a futsal context

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dominance and Subordination Interactions Among Nestmates in Pre and Post-Emergence Phases of the Basal Eusocial Wasp Mischocyttarus (Monogynoecus) montei (Hymenoptera, Vespidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Androgen receptor in the Mongolian gerbil ventral prostate: Evaluation during different phases of postnatal development and following androgen blockage

The normal growth, differentiation and maintenance of the morphofunctional integrity of the prostate gland are dependent on the interaction of constant levels of androgens with their receptors. The need to study the responses to hormones under several conditions and the effect of their blockage is due to the fact that the human prostate is the site of a great number of age-related diseases, and the ones with a major medical importance are prostate cancer (Cap) and benign prostatic hyperplasia (BPH), which can both be treated with androgen suppression. Seventy-five male gerbils were divided, randomly, into 3 groups of 25 animals each, where each group corresponded to one phase of postnatal development. In each phase, it was possible to morphologically and stereologically analyze the compartments of prostatic ventral lobe, as well as to immunohistochemically analyze the degree of expression of androgen receptors (ARs) after the androgen blockage therapies. In addition, it was possible to establish the hormonal dosage of serum testosterone levels given the comparative approach of the expression of androgen receptors. There is a pattern of AR distribution in the prostatic ventral lobe throughout postnatal development, in which the younger the animal is the higher, the interaction of circulating androgens that stimulate the AR expression in both the epithelial and stromal compartments. The androgen blockage therapies decreased AR expression in the prostatic compartments, but the androgen reposition after these blockages was not sufficient to recover the glandular structure or stimulate the AR expression up to normal physiological conditions. Both the regulation and distribution of androgen receptors along the gerbil prostatic tissues are complex mechanisms that are likely to be genetically regulated by androgens prenatally or by other factors that are still unknown. This rodent species seems to be a valuable model in the attempt to improve the understanding of the morphophysiological and pathological behavior of this important gland in humans throughout aging and to stimulate new therapeutic ideas to fight prostate cancer. (C) 2008 Elsevier Ltd. All rights reserved.

Phase behavior of the orange essential oil/sodium bis(2-ethylhexyl)sulfosuccinate/water system

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Plasmid DNA partitioning and separation using poly(ethylene glycol)/poly(acrylate)/salt aqueous two-phase systems

Phase diagrams of poly(ethylene glycol)/polyacrylate/Na2SO4 systems have been investigated with respect to polymer size and pH. Plasmid DNA from Escherichia coil can depending on pH and polymer molecular weight be directed to a poly(ethylene glycol) or to a polyacrylate-rich phase in an aqueous two-phase system formed by these polymers. Bovine serum albumin (BSA) and E. coil homogenate proteins can be directed opposite to the plasmid partitioning in these systems. Two bioseparation processes have been developed where in the final step the pDNA is partitioned to a salt-rich phase giving a total process yield of 60-70%. In one of them the pDNA is partitioned between the polyacrylate and PEG-phases in order to remove proteins. In a more simplified process the plasmid is partitioned to a PEG-phase and back-extracted into a Na2SO4-rich phase. The novel polyacrylate/PEG system allows a strong change of the partitioning between the phases with relatively small changes in composition or pH. (C) 2012 Elsevier B.V. All rights reserved.

Global dynamics of stationary solutions of the extended Fisher-Kolmogorov equation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)