940 resultados para Initial stages


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The vitamins A and E are recognizably important in the initial stages of life and the newborn depends on nutritional adequacy of breast milk to meet their needs. These vitamins share routes of transport to the tissues and antagonistic effects have been observed in animals after supplementation with vitamin A. This study aimed to verify the effect of maternal supplementation with vitamin A megadose (200,000 UI) in the immediate post-partum on the concentration of alpha-tocopherol in colostrum. Healthy parturient women attended at a public maternity natalensis were recruited for the study and divided into two groups: control (n = 37) and supplemented (n = 36). Blood samples of colostrum and milk were collected until 12 hours after delivery. The women of the supplemented group was administered a retynil palmitate capsule and 24 hours after the first collection was obtained the 2nd sample of colostrum in two groups for analysis of retinol and alpha-tocopherol in milk. The mean retinol concentration of 50,7 ± 14,4 μg/dL (Mean ± standard deviation) and alpha-tocopherol of 1217.4 ± 959 mg/dL in the serum indicate the nutritional status biochemical appropriate. Supplementation with retynil palmitate resulted in increase not only retinol levels in the colostrum of the supplemented group (p = 0.002), but also the concentration of alpha-tocopherol (p = 0.04), changing from 1456.6 ± 1095.8 mg/dL to 1804.3 ± 1432.0 mg/dL (milk 0 and 24 respectively) compared to values in the control group, 984.6 ± 750.0 mg/dL and 1175.0 ± 730.8 mg/dL. The women had different responses to supplementation, influenced by baseline levels of retinol in colostrum. Those with previous by low levels of retinol in colostrum (<60 mg/dL) had increased the concentration of alpha-tocopherol in milk, whereas those with adequate levels (> 60 mg/dL), showed a reduction after supplementation. Supplementation with retinol palmitate is an important intervention in situations of high risk for vitamin A deficiency, when considering the need to maternal supplementation, since the excess vitamin can offer unfavorable interactions between nutrients essential for the mother-child group

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Flowering is controlled by several environmental and endogenous factors, usually associated with a complex network of metabolic mechanisms. The gene characterization in Arabidopsis model has provided much information about the genetic and molecular mechanisms that control flowering process. Some of these genes had been found in rice and maize. However, in sugarcane this processe is not well known. It is known that early flowering may reduce its production up to 60% at northeast conditions. Considering the impact of early flowering in sugarcane production, the aim of this work was to make the gene characterization of two cDNAs previously identified in subtractive cDNA libraries: scPKCI and scSHAGGY. The in silico analysis showed that these two cDNAs presented both their sequence and functional catalytic domains conserved. The results of transgenic plants containing the overexpression of the gene cassette scPKCI in sense orientation showed that this construction had a negative influence on the plant development as it was observed a decrease in plant height and leaf size. For the scPKCI overexpression in antisense orientation it was observed change in the number of branches from T1 transgenic plants, whereas transgenic T2 plants showed slow development during germination and initial stages of development. The other cDNA analyzed had homology to SHAGGY protein. The overexpression construct in sense orientation did not shown any effect on development. The only difference observed it was an increase in stigma structure. These results allowed us to propose a model how these two genes may be interact and affect floweringdevelopment.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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In the present work, tellurite 20Li(2)O-80TeO(2) glasses were prepared with identical nominal composition under different glass-forming histories to produce a stressed and stress-free samples. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) techniques were used to study the effects of the glass-forming histories on the thermal and structural properties of these glasses. The gamma-TeO2 (metastable), alpha-TeO2 and alpha-Li2Te2O5 phases were identified during the controlled devitrification in these glasses. The mestastable character of the gamma-TeO2 phase was clearly observed in the glass under stress but this effect is not so clear in the stress-free glass. The gamma-TeO2 and alpha-TeO2 phases crystallizes during the initial stages of crystallization in both studied glasses while the alpha-Li2Te2O5 phase crystallize in the final stages of the crystallization. The activation energies and Avrami exponent were calculated for both studied glasses with different particle size leading to E-3 > E-2 > E-1 for stressed glass and E-3 > E-2 approximate to E-1 for stress-free glass, where E-1, E-2 and E-3 were associated to the gamma-TeO2, alpha-TeO2 and alpha-Li2Te2O5 phases, respectively. The observed distinct (n) over bar (1) < <(n)over bar>(2) < <(n)over bar>(3) in both glasses is an indicative that nucleation and growth takes place by more than one mechanism in the early stages of the crystallization. (C) 2011 Elsevier B.V. All rights reserved.

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Currently with the increase in complexity in doing business, organizations are seeking information systems that help to quickly respond to new demands in the processes of production of products and services. An information system is no longer just a support tool and has become an integral part of doing business. However, in spite of significant technological evolution in recent years, information systems that support business do not respond efficiently to the constant alterations that occur in many organizations. One of the main problems faced by information systems currently is the lack of strategic alignment between business strategy and information technology. The concept of strategic alignment can be defined as a way between business strategies and objectives and the strategies, objectives and functions of information technology in such as way as to contribute to the increase in competitivity of the organization over time. Strategic alignment together with strategic planning are important management instruments. Approaches for operationalizing this alignment are being developed currently but are still in their initial stages due to the fact that it is a relatively new concept in the literature. Another point that needs to be taken into consideration during the strategic alignment is the question of trackability between the business elements and IT. Trackability (Tracking) is necessary for example when one wishes to know exactly which goal defined in the business strategy was left out or not accepted due to a modification made in the IT strategy. Very few proposals present concrete ways supported by software systems in order to obtain strategic alignement while taking into consideration this trackability. Therefore the objective of this work is to propose the creation of a strategic alignment process supported by a software system which is capable of permitting trackability between the organizational objectives and the business processes based on formalization standards defined through a model oriented approach

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Removing inconsistencies in a project is a less expensive activity when done in the early steps of design. The use of formal methods improves the understanding of systems. They have various techniques such as formal specification and verification to identify these problems in the initial stages of a project. However, the transformation from a formal specification into a programming language is a non-trivial task and error prone, specially when done manually. The aid of tools at this stage can bring great benefits to the final product to be developed. This paper proposes the extension of a tool whose focus is the automatic translation of specifications written in CSPM into Handel-C. CSP is a formal description language suitable for concurrent systems, and CSPM is the notation used in tools support. Handel-C is a programming language whose result can be compiled directly into FPGA s. Our extension increases the number of CSPM operators accepted by the tool, allowing the user to define local processes, to rename channels in a process and to use Boolean guards on external choices. In addition, we also propose the implementation of a communication protocol that eliminates some restrictions on parallel composition of processes in the translation into Handel-C, allowing communication in a same channel between multiple processes to be mapped in a consistent manner and that improper communication in a channel does not ocurr in the generated code, ie, communications that are not allowed in the system specification

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When crosscutting concerns identification is performed from the beginning of development, on the activities involved in requirements engineering, there are many gains in terms of quality, cost and efficiency throughout the lifecycle of software development. This early identification supports the evolution of requirements, detects possible flaws in the requirements specification, improves traceability among requirements, provides better software modularity and prevents possible rework. However, despite these several advantages, the crosscutting concerns identification over requirements engineering faces several difficulties such as the lack of systematization and tools that support it. Furthermore, it is difficult to justify why some concerns are identified as crosscutting or not, since this identification is, most often, made without any methodology that systematizes and bases it. In this context, this paper proposes an approach based on Grounded Theory, called GT4CCI, for systematizing and basing the process of identifying crosscutting concerns in the initial stages of the software development process in the requirements document. Grounded Theory is a renowned methodology for qualitative analysis of data. Through the use of GT4CCI it is possible to better understand, track and document concerns, adding gains in terms of quality, reliability and modularity of the entire lifecycle of software

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The need to become energy self-sufficient a country with which Brazil has sought renewable energy sources due to the possibility of depletion of oil in coming decades. This paper will examine the perspective of social inclusion the latest energy plan developed by the Federal Government: the National Program of Biodiesel Production and Use - PNPB. It aims to find out whether that work with family farmers who participated in the PNPB socially included and what limits its inclusion. Secondly, the objective is to analyze the Brazilian biodiesel production and its uses. The methodology used for the preparation of this study was to examine the literature, visits to the study area, conducting interviews with the leadership of the settlement, questionnaires and semi-structured interviews with families producing sunflower. Finally, the research dealt with the statistical data. After analyzing the data was verified that the instrument PNPB is able to promote the social inclusion of family farmers, but this occurred in the initial stages because the families involved need a minimum framework of organization and infrastructure to develop activities related to biodiesel

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The Xaréu Oil Field, located in the center-southern portion of the Mundaú Sub-Basin (eastern portion of the Ceará Basin), is characterized by a main Iramework of NW-trending and NE-dipping faults. The faults in the Xaréu Oil Field, among which the Xaréu Fautt stands out, are arranged according to an extensional-listriclan, rooted on a detachment surface corresponding to the Mundaú Fault, the border fautt of Mundaú Sub-Basin. During the tectonic-structural evolution of the Xaréu Oil Field and the Mundaú Sub-Basin, the Mundaú Fault played a crucial role on the control of the geometry of both compartments. The main carbonatic unit in the Xaréu Oil Field, named the Trairí Member(Paracuru Formation of Late Aptian to Early Albian age), contains the largest oil volume in the field, concentrated in structurally-controlled accumulations. The Trairí Member is composed by a variety of carbonatic rocks (massive, bedded or laminated calcilutites, ostracodites, calcarenites and carbonatic rudites, all of them presenting variable degrees of dolomitization). The carbonatic rocks are interbedded into thick packages of black shales and marls, besides local beds of siliciclastic conglomerates, sandstones, siltnes and argillites. From the spatial association and the genetic relationships between the carbonatic and siliciclastic units, it is possible to group them in three lithofacies associations (Marginal Plain, Ramp and Lacustrine Interior) that, together, were developed in a lacustrine system associated to a marginal sabkha. Structural studies based on drill coresthat sample the Trairí Member in the Xaréu Oil Field allowed to characterize two generations of meso- to microscale structures: the D1 group presents a typical hydroplastic character, being characterized by intra/interstratal to oblique-bedding shear zones. The hydroplastic character related to these structures allowed to infer their development at an early-lithilication stage of the Trairí Member, leading to infer an Early Cretaceous age to them. The second group of structures identified in the drill cores, nominated D2 and ascribed to a Neogene age, presents a strictly brttle character, being typilied by normal faults and slickenfibers of re-crystallized clayminerals, ali olthem displaying variable orientations. Although the present faults in the Xaréu Oil Field (and, consequently, in the Mundaú Sub-Basin) were classically relerred as struetures of essentially normal displacement, the kinematics analysis of the meso-to microscaie D1 struetures in the drill cores led to deline oblique displacements (normal with a clockwise strike-slip component) to these faults, indicating a main tectonic transport to ENE. These oblique movements would be responsible for the installation of a transtensive context in the Mundaú Sub-Basin, as part of the transcurrent to translormant opening of the Atlantic Equatorial Margin. The balancing of four struetural cross-sections ofthe Xaréu Oil Field indicates that the Mundaú Fault was responsible for more than 50% of the total stretching (ß factor) registered during the Early Aptian. At the initial stages of the "rifting", during Early Aptianuntil the Holocene, the Mundaú Sub-Basin (and consequently the Xaréu Oil Fleld) accumulated a total stretching between 1.21 and 1.23; in other words, the crust in this segment of the Atlantic Equatorial Margin was subjeeted to an elongation of about 20%. From estimates of oblique displacements related to the faults, it ws possible to construct diagrams that allow the determination of stretching factors related to these displacements. Using these diagrams and assuming the sense 01 dominant teetonictransport towards ENE, it was possible to calculate the real stretching lactors related to the oblique movement 0 of the faults in the Mundaú Sub-Basin. which reached actual values between 1.28 and 1.42. ln addnion to the tectonic-structural studies in the Xaréu Oil Field, the interpretation of remote sensing products, coupled wnh characterization of terrain analogues in seleeted areas along the northern Ceará State (continental margins of the Ceará and Potiguar basins), provided addnional data and constraints about the teetonic-structural evolution of the oil lield. The work at the analogue sites was particularly effective in the recognition and mapping, in semidetail scale, several generations of struetures originated under a brittle regime. Ali the obtained information (from the Xaréu Oil Field, the remote sensor data and the terrain analogues) were jointly interpreted, culminating with the proposnion of an evolutionary model lor this segment of the Atlantic Equatorial Margin; this model that can be applied to the whole Margin, as well. This segmentof the Atlantic Equatorial Margin was delormedin an early E-W (when considered lhe present-day position of the South American Plate) transcurrent to transform regime with dextral kinematics, started Irom, at least, the Early Aptian, which left its record in several outcrops along the continental margin of the Ceará State and specilically in the Xaréu off Field. The continuous operation of the regime, through the Albian and later periods, led to the definitive separation between the South American and African plates, with the formation of oceanic lithosphere between the two continental blocks, due to the emplacement off spreading centers. This process involved the subsequent transition of the transcurrent to a translorm dextral regime, creating lhe Equatorial Atlantic Oceano With the separation between the South American and African plates already completed and the increasing separation between lhe continental masses, other tecton ic mechanisms began to act during the Cenozoic (even though the Cretaceous tectonic regime lasted until the Neogene), like an E-W compressive stress líeld (related to the spreading olthe oceanic floor along lhe M id-Atlantic Ridge and to the compression of the Andean Chain) effective Irom the Late Cretaceous, and a state of general extension olthe horizontal surface (due to the thermal uplift ofthe central portion of Borborema Province), effective during the Neogene. The overlap of these mechanisms during the Cenozoic led to the imprint of a complex tectonic framework, which apparently influenced the migration and entrapment 01 hydrocarbon in the Ceará Basin

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Objective. The aim of this study was to detect the development of experimentally induced periapical lesions using conventional radiography and computed tomography.Study design. The root canals of dogs' teeth were exposed to the oral environment for 7 days for contamination and then sealed for 7 days (GI), 15 days (GII), 30 days (GIII), and 60 days (GIV). Immediately after each experimental period, radiographs and tomograms were taken in order to detect the occurrence of periapical bone resorption. The periapical radiographs were digitized and areas of bone resorption were measured using the VIXWIN 2000 software. Scores were assigned to the tomograms based on the progression of periapical bone resorption. The specimens were evaluated by calibrated examiners who were blinded to the groups. The radiographic results were analyzed by ANOVA and Tukey's test (P <.05) and the tomographic results were analyzed by Kruskal-Wallis and Dunn's tests (P <.05).Results. The radiographic evaluation did not reveal periapical lesions at the 7-day control. Lesions were radiographically visible at 15 and 30 days (47.4% and 77.8% of the cases, respectively) and presented similar dimensions (P <.05). At 60 days, lesions were detected in all specimens, presenting larger dimensions than those of the earlier evaluation periods (P <.05). The tomographic evaluation detected lesions at 7 and 15 days (32.5% and 83.3% of the cases, respectively). Lesions were detected in all specimens at the 30- and 60-day periods, when the greatest values of bone resorption were observed (P <.05).Conclusions. Tomography was able to detect periapical lesion development in its initial stages, even when the lesions were undetectable radiographically.

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Objective. The present study evaluated the dynamics of the development of periapical lesions.Study design. Root canals from dogs' teeth were exposed to the oral environment, and then sealed for 7 days (Group A), 15 days (Group B), 30 days (Group C), and 60 days (Group D). After each experimental period, radiographs were taken to detect periapical bone resorption. In addition, histological sections from the periapical region were prepared. The radiographic and histological results were analyzed by ANOVA and Tukey's, Wilcoxon, and Pearson's tests. Significance level was set at 5%.Results. Lesions were radiographically visible at 15 and 30 days, and had similar size at these periods (P > .05). At 60 days, lesions were larger than in the other periods (P < .05). Bone resorption was detected histologically at 7 days. The greatest values of bone resorption were observed at the 30- and 60-day periods (P < .05). The results of the methods of evaluation were similar only at the 30-day period. There was no correlation between the radiographic and histological results.Conclusions. Periapical radiography did not provide detection of periapical lesion in its initial stages. The periapical lesions became more evident radiographically when the bone resorption area increased. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;107:442-447)

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Cell lysis in the formation of secretory cavities in plants has been questioned by some authors and considered as result of technical artifacts. To describe the formation of secretory resin cavities in Hymenaea stigonocarpa leaves, leaflet samples at different stages of differentiation were collected, fixed, and processed for light and electron microscopy as per usual methods. The initial cells of secretory resin cavities are protodermal and grow towards the mesophyll ground meristem; these cells then divide producing cell groups that are distinguished by the shape and arrangement of cytoplasm, and density. At the initial stages of differentiation of the secretory cavities, some central cells in these groups show dark cytoplasm and condensed nuclear chromatin. Later, there is cell wall loosening, tonoplast and plasmalemma rupture resulting in cell death. These cells, however, maintain organelle integrity until lysis, when the cell wall degrades and the plasmalemma ruptures, releasing protoplast residues, marked characteristics of programmed cell death. The secretory epithelium remains active until complete leaf expansion when the cavity is filled with resin and the secretory activity ceases. There are no wall residues between central cells in adult cavities. Our results demonstrate lysigeny and the importance of ontogenetic studies in determining the origin of secretory cavities.

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The chemical interaction between plants is known as allelopathy and it is related to the release of substances into the environment. The present study aimed at the evaluation of the allelopathic activity of the leaves of Leonurus sibiricus against the germination and initial growth of Raphanus sativus, Lactuca sativa, and Lepidium sativum. Chemical analyses showed the presence in the leaves of four major flavonoids (quercetin-3-O-alpha-L-rhamnopyranosyl-(1 > 6)-beta-D-galactopyranoside; rutin; hyperin, and isoquercetrin) and of three minor flavonoidic compounds (genkwanin, 3'-hydroxy genkwanin, and quercetin). Extracts, their chromatographic fractions and pure isolated flavonoids showed different biological activities. A methanol extract of leaves of Leonurus sibiricus caused significant reduction only in the germination of Lactuca sativa, with no effects on the germinative processes of Raphanus sativus and Lepidium sativum. Some chromatographic fractions, containing the flavonoids, showed inhibitory activity on the initial stages of root growth of all tested seeds. The isolated flavonoids, at the higher concentration tested (10(-4) M) seemed to be responsible for the inhibition of the germination, as well as the radical elongation. Among pure compounds, 3'-OH-genkwanin and quercetin showed the stronger antigerminative activity at the concentration of 10(-4) M, whereas the radical elongation was reduced by rutin, isoquercetrin and 3'-OH-genkwanin. All compounds, tested at concentrations ranging between 10(-5) and 10(-7) M, showed stimulatory activities.

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The modern approach to the development of new chemical entities against complex diseases, especially the neglected endemic diseases such as tuberculosis and malaria, is based on the use of defined molecular targets. Among the advantages, this approach allows (i) the search and identification of lead compounds with defined molecular mechanisms against a defined target (e.g. enzymes from defined pathways), (ii) the analysis of a great number of compounds with a favorable cost/benefit ratio, (iii) the development even in the initial stages of compounds with selective toxicity (the fundamental principle of chemotherapy), (iv) the evaluation of plant extracts as well as of pure substances. The current use of such technology, unfortunately, is concentrated in developed countries, especially in the big pharma. This fact contributes in a significant way to hamper the development of innovative new compounds to treat neglected diseases. The large biodiversity within the territory of Brazil puts the country in a strategic position to develop the rational and sustained exploration of new metabolites of therapeutic value. The extension of the country covers a wide range of climates, soil types, and altitudes, providing a unique set of selective pressures for the adaptation of plant life in these scenarios. Chemical diversity is also driven by these forces, in an attempt to best fit the plant communities to the particular abiotic stresses, fauna, and microbes that co-exist with them. Certain areas of vegetation (Amazonian Forest, Atlantic Forest, Araucaria Forest, Cerrado-Brazilian Savanna, and Caatinga) are rich in species and types of environments to be used to search for natural compounds active against tuberculosis, malaria, and chronic-degenerative diseases. The present review describes some strategies to search for natural compounds, whose choice can be based on ethnobotanical and chemotaxonomical studies, and screen for their ability to bind to immobilized drug targets and to inhibit their activities. Molecular cloning, gene knockout, protein expression and purification, N-terminal sequencing, and mass spectrometry are the methods of choice to provide homogeneous drug targets for immobilization by optimized chemical reactions. Plant extract preparations, fractionation of promising plant extracts, propagation protocols and definition of in planta studies to maximize product yield of plant species producing active compounds have to be performed to provide a continuing supply of bioactive materials. Chemical characterization of natural compounds, determination of mode of action by kinetics and other spectroscopic methods (MS, X-ray, NMR), as well as in vitro and in vivo biological assays, chemical derivatization, and structure-activity relationships have to be carried out to provide a thorough knowledge on which to base the search for natural compounds or their derivatives with biological activity.