710 resultados para Prematuridade : Interacao mae-bebe


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Vitamin A is an essential nutrient for many physiological processes such as growth and development, so that their adequate nutritional state is essential during pregnancy and lactation. Lactating women and children in breastfeeding are considered risk groups for vitamin A deficiency and some factors may increase the risk of vitamin A deficiency, such as prematurity. The aim of this work was to evaluate the vitamin A concentration in preterm and term lactating women and newborns by determination of retinol in maternal serum, umbilical cord serum and breast milk collected until 72 hours postpartum. 182 mothers were recruited and divided into preterm group (GPT; n = 118) and term group (GT, n = 64). In preterm group were also analyzed transition milk (7th-15th day; n = 68) and mature milk (30th-55th day; n = 46) samples. Retinol was analyzed by high-performance liquid chromatography (HPLC). Maternal retinol concentration in serum was 48.6 ± 12.3 µg/dL in GPT and 42.8 ± 16.3 µg/dL in the GT (p <0.01). Cord serum retinol was 20.4 ± 7.4 µg/dL in GPT and 23.2 ± 7.6 µg/dL in GT (p> 0.05). Among newborns, 43% of premature and 36% of term had low levels of serum retinol in umbilical cord (<20 µg/dL). In colostrum, the retinol in preterm and term groups had an average of 100.8 ± 49.0 µg/dL and 127.5 ± 65.1 µg/dL, respectively (p <0.05). The retinol average in preterm milk increased to 112.5 ± 49.7 µg/dL in transition phase and decreased to 57.2 ± 23.4 µg/dL in mature milk, differing significantly in all stages (p <0.05). When comparing with the recommendation of vitamin A intake (400 µg/day) GT colostrum reached the recommendation for infants, but in GPT the recommendation was not achieved at any stage. Mothers of premature infants had higher serum retinol than mothers at term; however, this was not reflected in serum retinol of umbilical cord, since premature had lower concentration of retinol. Such condition can be explained due to lower maternal physiological hemodilution and placental transfer of retinol to the fetus during preterm gestation. Comparison of retinol in colostrum showed lower concentrations in GPT; however the transition phase there was a significant increase of retinol content released by the mammary gland of preterm mothers. This situation highlights a specific physiological adaptation of prematurity, likely to more contribute to formation of hepatic reserves of retinol in premature infants.

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The Nb-Cu pseudoalloys present themselves as potential substitutes for the alloys from a well known system and already commercially applied, as the W-Cu alloys, used in applications such as heat sinks, electrical contacts and coils for the generation of high magnetic fields. Because it is an immiscible system, where there is mutual insolubility and low wettability of the liquid Cu on the Nb surface, the processing route used in this work was the Powder Metallurgy. Two Nb alloys were used, with additions of 10% and 20% in weight of Cu, and times of 20, 30 and 40 hours for the high energy milling of the starting powders. The milling evolution of the powders is presented through the characterization techniques, such as the LASER diffraction for particle size, XRD, SEM, EDS, DSC, dilatometry, TEM and chemical analysis. After the milling, portions of the loads were submitted to the annealing heat treatment. The process used for the samples consolidation was the hot pressing, which has been applied both on some milled powders samples, as on the annealed powders. Subsequent heat treatments were performed in the samples at temperatures of 1000ºC (solid phase) and 1100ºC (in the Cu liquid phase). All sets of consolidated samples, and also the two sets of the heat treated, were analyzed by XRD, SEM, EDS, density and Vickers microhardness. Moreover, other Nb powder samples with 10% and 20% in weight of Cu obtained by simple mechanical mixing, were consolidated, thermally treated and characterized with the same techniques applied to the others, and the results were compared among themselves. Despite the difficulty of consolidation and densification of the two pseudoalloys of the Nb-Cu system of this study, on the route that passes through the HEM, samples were obtained with densities around 90% of the theoretical density. And, on the processing route of which were only mixed, the values reached up to 97%. Therefore, in this work are also emphasized the processes that made possible these results.

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Composites based on alumina (Al2O3), tungsten carbide (WC) and cobalt (Co) exhibit specific properties such as low density, high oxidation resistance, high melting point and high chemical inertia. That composite shows to be a promising material for application in various fields of engineering. In this work, the mechanical properties of the composite (Al2O3 – WC – Co), particularly density and hardness, were evaluated according to the effects of the variables of powder processing parameters, green compact and sintered. Powder composites with the composition of 80 wt% Al2O3, 18 wt% WC and 2 wt% Co were processed by high energy ball milling in a planetary mill for 50 hours as well as mixed by manual mixing in a glass vessel with the same proportion. Samples were collected (2, 10, 20, 30, 40 and 50 hours) during the milling process. Then, the powders were compacted in a cylindrical die with 5 mm in diameter in a uniaxial press with pressures of 200 and 400 MPa. The sintering was in two stages: first, the solid phase sintering was performed at 1126 and 1300 °C for 1 hour with a heating rate of 10 °C/min in a resistive furnace under argon atmosphere for green samples compacted in 200 and 400 MPa; the second sintering was performed on dilatometer in solid phase at 1300 °C for green sample compacted in 200 MPa, another sintering also was performed on dilatometer, this time in liquid phase at 1550 °C for green samples compacted in 200 and 400 MPa, with the same parameters used in resistive furnace. The raw materials were characterized by X – ray diffraction (XRD), X – ray fluorescence (XRF), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and laser particlemeter. The sintered samples were subjected to microhardness testing. The results showed that high energy milling achieved to the objectives regarding the particle size and the dispersion of composite phases. However, the hardness did not achieve to significant results, this is an indication that the composite has low fracture toughness.

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Composites based on alumina (Al2O3), tungsten carbide (WC) and cobalt (Co) exhibit specific properties such as low density, high oxidation resistance, high melting point and high chemical inertia. That composite shows to be a promising material for application in various fields of engineering. In this work, the mechanical properties of the composite (Al2O3 – WC – Co), particularly density and hardness, were evaluated according to the effects of the variables of powder processing parameters, green compact and sintered. Powder composites with the composition of 80 wt% Al2O3, 18 wt% WC and 2 wt% Co were processed by high energy ball milling in a planetary mill for 50 hours as well as mixed by manual mixing in a glass vessel with the same proportion. Samples were collected (2, 10, 20, 30, 40 and 50 hours) during the milling process. Then, the powders were compacted in a cylindrical die with 5 mm in diameter in a uniaxial press with pressures of 200 and 400 MPa. The sintering was in two stages: first, the solid phase sintering was performed at 1126 and 1300 °C for 1 hour with a heating rate of 10 °C/min in a resistive furnace under argon atmosphere for green samples compacted in 200 and 400 MPa; the second sintering was performed on dilatometer in solid phase at 1300 °C for green sample compacted in 200 MPa, another sintering also was performed on dilatometer, this time in liquid phase at 1550 °C for green samples compacted in 200 and 400 MPa, with the same parameters used in resistive furnace. The raw materials were characterized by X – ray diffraction (XRD), X – ray fluorescence (XRF), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and laser particlemeter. The sintered samples were subjected to microhardness testing. The results showed that high energy milling achieved to the objectives regarding the particle size and the dispersion of composite phases. However, the hardness did not achieve to significant results, this is an indication that the composite has low fracture toughness.

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Acknowledgements The Authors are indebted with Dr. Barbara Cerasetti, scientific coordinator of the Italian Archaeological Program in Turkmenistan (Dipartimento di Storia, Culture, Civiltà – Università di Bologna – Ministero per gli Affari Esteri – MAE), for the logistical help before and during the field activities in Turkmenistan. Our thanks to the administration of the National Institute of Deserts, Flora and Fauna, to the Turkmenistan Government and to Dr Aman Nigarov for the fruitful assistance in the field. We thank Prof. Marco Antonellini for the discussions on sandstone intrusions. The authors are indebted to the reviewers J. Peakall, P. Imbert, A. Hurst and an anonymous reviewer for the very helpful comments to the manuscript. Funding was provided by Prof. G. Gabbianelli for the field survey and by PRIN 2009 grants to Prof. Rossella Capozzi.

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The Singapore Cohort Study of the Risk Factors for myopia (SCORM) is a longitudinal school-based study that recruited 1979 children, aged 7 to 9 years old between 1999 and 2001, who were re-examined as adolescents in 2006 and 2007. This current study is to determine the prevalence, incidence and progression of myopia among Singapore teenagers and describe any trend in the SCORM study.

At each visit, participants underwent comprehensive eye examinations that included cycloplegic autorefraction and ocular biometry measurements. The prevalence of myopia (SE<-0.5D) and high myopia (SE<-6.0D) among Singapore teenagers aged 11-18 years old was 69.1% [95% confidence interval (CI) 66.5-71.7] and 7.1% (95% CI 5.8-8.7), respectively, with the highest prevalence in people of Chinese ethnicity (p<0.001). The annual incidence was 13.7% (95% CI 9.8-17.6). Males had twice the incidence of females (p=0.043), and adolescents with longer axial lengths (p<0.001) and deeper vitreous chamber (p<0.001) had higher myopia incidence. Annual myopia progression was -0.32 Diopters (D) (SD=0.40), with no difference by age, race or gender. However, adolescents with higher myopia levels at 2006 had significantly faster myopia progression rates (p<0.001).

Myopia prevalence in Singapore teenagers, especially Singapore Chinese teenagers, is one of the highest in the world. In adolescents, there is still a high rate of new onset and rapid progression of myopia. These findings indicate that adolescence may still represent a viable period for intervention programs to mitigate myopia onset and progression.

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Die Sandergebiete sind von 5 Zentren her geschüttet, den Gletschertoren bei Flensburg, Frörup/Översee, Idstedt/Lürschau, Schleswig, Owschlag. Die Körnung der Schmelzwassersande nimmt mit zunehmender Entfernung von den Gletschertoren zunächst schnell, von Medianwerten über 1 mm auf Medianwerte um 0,4 mm in 10 km, dann langsam bis auf Medianwerte unter 0,2 mm in 30 km Entfernung ab. Sortierung und Symmetrie der Sande steigen entsprechend. Aus den Kornverteilungen lassen sich die Fließgeschwindigkeiten bei der Ablagerung ablesen. Sie sind geringer gewesen, als es die mächtigen und verbreiteten Akkumulationen erscheinen lassen. Bereits in 6 km Entfernung vom Eisrand flossen die Schmelzwässer als träge Bäche (0,3 m/sec) ab. In den Gletschertoren traten stoßweise extreme Fließgeschwindigkeiten auf, waren aber nur in geringem Maße am Gesamtaufbau der Sander beteiligt. Die Verbreitung der Würmsande paßt sich den Formen einer älteren Landschaft an. Sie läßt sich im behandelten Gebiet mit Hilfe der Schwermineralanalyse deutlich gegenüber den rißzeitlichen Ablagerungen abgrenzen, da die Verteilungen in den verschiedenaltrigen Sedimenten unterschiedlich sind. Vor Allem das Hornblende/Epidotverhältnis (Hornblendezahl nach STEINERT) ist ein gutes Kriterium. Da rißzeitliche Ablagerungen von den Schmelzwässern aufgearbeitet wurden, und zudem die Hornblenden im Laufe des Transportes stark abrollen, verwischen sich die Unterschiede in weiter Entfernung vom Eisrand. Schmelzwassersande der Würmvereisung sind vor Allem im Norden des Arbeitsgebietes weit nach Westen, bis an die nordfriesischen Inseln, geschüttet worden. Die Schmelzwässer benutzten als Durchlässe zu den Senken des Eemmeeres an der Westküste Täler in rißzeitlichen Hochgebieten. Die Wassermengen wurden hier gebündelt, sodaß sich auf den Eemablagerungen im Anschluß an die Durchlässe "Sekundärsander" ausbreiteten. Die Mächtigkeit der anstehenden Würm-Sandergebiete beträgt bis zu 20 m, meistens zwischen 10 und 15 m. An der Westküste sind die Schmelzwasserablagerungen von marinem Alluvium überdeckt. Teile der morphographisch als junge Sanderebenen erscheinenden Gebiete bestehen in Wirklichkeit aus rißzeitlichen, von jungen Schmelzwässern allenfalls oberflächlich umgearbeiteten Ablagerungen der älteren Vereisung. So ist der westliche und südwestliche Teil des Schleisanders schon während der Rißvereisung aufgeschüttet.

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Las épocas de crisis político-social propician en especial medida la creación y el afianzamiento de determinados auto y heteroestereotipos. Esta afirmación resulta concluyente cuando se analiza cómo las distintas fases políticas de España a lo largo de la historia han condicionado de manera definitiva su imagen en el extranjero, en especial en Alemania. Las imágenes y estereotipos románticos creados a partir de la Guerra de la Independencia (1808-1814) sirvieron durante la primera mitad del siglo veinte de instrumento de manipulación propagandística que debía contribuir a ensalzar la ejemplaridad del aliado español. Este artificio político, que buscaba la simpatía ideológica con el sistema de valores nacionalsocialista, se valió de manera particular de las producciones cinematográficas hispano-alemanas para lograr su objetivo.

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Die Fähigkeit, geschriebene Texte zu verstehen, d.h. eine kohärente mentale Repräsentation von Textinhalten zu erstellen, ist eine notwendige Voraussetzung für eine erfolgreiche schulische und außerschulische Entwicklung. Es ist daher ein zentrales Anliegen des Bildungssystems Leseschwierigkeiten frühzeitig zu diagnostizieren und mithilfe zielgerichteter Interventionsprogramme zu fördern. Dies erfordert ein umfassendes Wissen über die kognitiven Teilprozesse, die dem Leseverstehen zugrunde liegen, ihre Zusammenhänge und ihre Entwicklung. Die vorliegende Dissertation soll zu einem umfassenden Verständnis über das Leseverstehen beitragen, indem sie eine Auswahl offener Fragestellungen experimentell untersucht. Studie 1 untersucht inwieweit phonologische Rekodier- und orthographische Dekodierfertigkeiten zum Satz- und Textverstehen beitragen und wie sich beide Fertigkeiten bei deutschen Grundschüler(inne)n von der 2. bis zur 4. Klasse entwickeln. Die Ergebnisse legen nahe, dass beide Fertigkeiten signifikante und eigenständige Beiträge zum Leseverstehen leisten und dass sich ihr relativer Beitrag über die Klassenstufen hinweg nicht verändert. Darüber hinaus zeigt sich, dass bereits deutsche Zweitklässler(innen) den Großteil geschriebener Wörter in altersgerechten Texten über orthographische Vergleichsprozesse erkennen. Nichtsdestotrotz nutzen deutsche Grundschulkinder offenbar kontinuierlich phonologische Informationen, um die visuelle Worterkennung zu optimieren. Studie 2 erweitert die bisherige empirische Forschung zu einem der bekanntesten Modelle des Leseverstehens—der Simple View of Reading (SVR, Gough & Tunmer, 1986). Die Studie überprüft die SVR (Reading comprehension = Decoding x Comprehension) mithilfe optimierter und methodisch stringenter Maße der Modellkonstituenten und überprüft ihre Generalisierbarkeit für deutsche Dritt- und Viertklässler(innen). Studie 2 zeigt, dass die SVR einer methodisch stringenten Überprüfung nicht standhält und nicht ohne Weiteres auf deutsche Dritt- und Viertklässler(innen) generalisiert werden kann. Es wurden nur schwache Belege für eine multiplikative Verknüpfung von Dekodier- (D) und Hörverstehensfertigkeiten (C) gefunden. Der Umstand, dass ein beachtlicher Teil der Varianz im Leseverstehen (R) nicht durch D und C aufgeklärt werden konnte, deutet darauf hin, dass das Modell nicht vollständig ist und ggf. durch weitere Komponenten ergänzt werden muss. Studie 3 untersucht die Verarbeitung positiv-kausaler und negativ-kausaler Kohärenzrelationen bei deutschen Erst- bis Viertklässler(inne)n und Erwachsenen im Lese- und Hörverstehen. In Übereinstimmung mit dem Cumulative Cognitive Complexity-Ansatz (Evers-Vermeul & Sanders, 2009; Spooren & Sanders, 2008) zeigt Studie 3, dass die Verarbeitung negativ-kausaler Kohärenzrelationen und Konnektoren kognitiv aufwändiger ist als die Verarbeitung positiv-kausaler Relationen. Darüber hinaus entwickelt sich das Verstehen beider Kohärenzrelationen noch über die Grundschulzeit hinweg und ist für negativ-kausale Relationen am Ende der vierten Klasse noch nicht abgeschlossen. Studie 4 zeigt und diskutiert die Nützlichkeit prozess-orientierter Lesetests wie ProDi- L (Richter et al., in press), die individuelle Unterschiede in den kognitiven Teilfertigkeiten des Leseverstehens selektiv erfassen. Hierzu wird exemplarisch die Konstruktvalidität des ProDi-L-Subtests ‚Syntaktische Integration’ nachgewiesen. Mittels explanatorischer Item- Repsonse-Modelle wird gezeigt, dass der Test Fertigkeiten syntaktischer Integration separat erfasst und Kinder mit defizitären syntaktischen Fertigkeiten identifizieren kann. Die berichteten Befunde tragen zu einem umfassenden Verständnis der kognitiven Teilfertigkeiten des Leseverstehens bei, das für eine optimale Gestaltung des Leseunterrichts, für das Erstellen von Lernmaterialien, Leseinstruktionen und Lehrbüchern unerlässlich ist. Darüber hinaus stellt es die Grundlage für eine sinnvolle Diagnose individueller Leseschwierigkeiten und für die Konzeption adaptiver und zielgerichteter Interventionsprogramme zur Förderung des Leseverstehens bei schwachen Leser(inne)n dar.

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My thesis explores the formation of the subject in the novels of Faulkner’s Go Down, Moses, Toni Morrison’s Song of Solomon, and Gloria Naylor’s Mama Day. I attach the concept of property in terms of how male protagonists are obsessed with materialistic ownership and with the subordination of women who, as properties, consolidate their manhood. The three novelists despite their racial, gendered, and literary differences share the view that identity and truth are mere social and cultural constructs. I incorporate the work of Judith Butler and other poststructuralist figures, who see identity as a matter of performance rather than a natural entity. My thesis explores the theme of freedom, which I attached to the ways characters use their bodies either to confine or to emancipate themselves from the restricting world of race, class, and gender. The three novelists deconstruct any system of belief that promulgates the objectivity of truth in historical documents. History in the three novels, as with the protagonists, perception of identity, remains a social construct laden with distortions to serve particular political or ideological agendas. My thesis gives voice to African American female characters who are associated with love and racial and gender resistance. They become the reservoirs of the African American legacy in terms of their association with the oral and intuitionist mode of knowing, which subverts the male characters’ obsession with property and with the mainstream empiricist world. In this dissertation, I use the concept of hybridity as a literary and theoretical devise that African-American writers employ. In effect, I embark on the postcolonial studies of Henry Louise Gates, Paul Gilroy, W. E. B Du Bois, James Clifford, and Arjun Appadurai in order to reflect upon the fluidity of Morrison’s and Naylor’s works. I show how these two novelists subvert Faulkner’s essentialist perception of truth, and of racial and gendered identity. They associate the myth of the Flying African with the notion of hybridity by making their male protagonists criss-cross Northern and Southern regions. I refer to Mae Gwendolyn Henderson’s article on “Speaking in Tongues” in my analysis of how Naylor subverts the patriarchal text of both Faulkner and Morrison in embarking on a more feminine version of the flying African, which she relates to an ex-slave, Sapphira Wade, a volatile female character who resists fixed claim over her story and identity. In dealing with the concept of hybridity, I show that Naylor rewrites both authors’ South by making Willow Springs a more fluid space, an assumption that unsettles the scores of critics who associate the island with authenticity and exclusive rootedness.

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Like many Americans across the country, Michigan residents have faced a staggering number of foreclosures in the last few years.2 In 2009, Laura Buttazzoni was one of the many Michigan homeowners facing the dire reality that she was going to lose her home.3 After Buttazzoni’s failed attempt to sell her home, her bank initiated a sheriff’s sale in late 2009.4 After the statutory redemption period expired,5 Fannie Mae evicted Buttazzoni and relisted the home in 2011.6 Even though Buttazzoni’s home was foreclosed, sold at a sale, and relisted on the market—she was not done with the property. In June 2012, nearly three years after Buttazzoni’s eviction, Fannie Mae executed an “expungement affidavit,” which voided the 2009 sheriff’s sale and reverted the mortgage back to Buttazzoni’s name.

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v. 46, n. 2, p. 140-148, apr./jun. 2016.

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Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a naïve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model

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Nos últimos anos, tem-se assistido a um crescimento no interesse do estudo da ressuspensão de pó de estrada, dado o reconhecimento da importância que esta fração representa para os níveis de partículas atmosféricas em ambiente urbano. Dada a prematuridade deste tema e, de forma a compreender e conhecer a sua contribuição e caracterização, realizou-se um estudo sobre a ressuspensão de pó de estrada urbano para as cidades do Porto e Braga. No âmbito do projeto AIRUSE e URBE, realizaram-se amostragens de PM10 no terreno com um dispositivo de amostragem móvel e em ambiente laboratorial com uma câmara de ressuspensão, sendo posteriormente analisado o seu conteúdo carbonoso por um sistema de análise termo-ótico de transmitância e, os elementos por ICP-MS e ICP-AES. Da campanha in situ resultaram cargas de PM10 compreendidas entre 0.190 e 49.5 mg.m-2 para a cidade do Porto e 0.577 mg.m-2 para o túnel rodoviário em Braga. As amostras caracterizam-se por serem dominadas pelos elementos Al, Fe, K, e Ca e conterem enriquecimentos de Sb, Fe, Cu, Sn e Zn, fruto da contaminação antropogénica da atividade rodoviária. No que respeita às amostragens em laboratório, utilizou-se uma câmara de ressuspensão e o dispositivo móvel aplicado na campanha anteriormente descrita para estudar e caracterizar a fração PM10 do pó de estrada urbano proveniente do Túnel Avenida da Liberdade (Braga). Os resultados obtidos para as duas metodologias foram de um modo geral similares, com o carbono total a representar cerca de 6% da massa total de PM10. Esta última é composta maioritariamente por Al, Fe, Ca e K, elementos característicos da crosta terrestre. Quanto ao fatores de enriquecimento calculados, denotou-se a presença de Sb, Zn, Cu e Sn, tendo-se associando ao desgaste dos travões e pneus.