Avaliação da suplementação de vitamina E sobre a concentração de alfa-tocoferol no leite materno em mulheres com partos prematuros

The term vitamin E refers to a group of eight molecular compounds which differ in structure and bioavailability, and the RRR-alpha-tocopherol more biologically active form. The composition of vitamin E in breast milk undergoes variations during lactation, colostrum and milk richer in this micronutrient compared to transitional and mature milk. Newborns, especially premature infants are more susceptible to vitamin E deficiency and to prevent the damage caused by this deficiency has been proposed supplementation of neonates with this micronutrient, however, there is no consensus to carry out this intervention. Thus, maternal supplementation with RRRalpha-tocopherol in the postpartum period can be a good alternative to try to raise the alpha-tocopherol levels in breast milk and therefore provide the premature newborn adequate amounts of vitamin E. This study to evaluate the effect of supplementation with 400 UI acetate RRR-alpha-tocopherol in women with premature births, on the concentration of alpha-tocopherol in breast milk colostrum, transitional and mature. The study included 89 healthy adult women were enrolled in the control group (n = 51) and supplemented group (n = 38). Blood samples were collected and milk colostrum soon after birth (0h milk) twenty-four hours, new rate of colostrum milk was collected (24h milk). The transitional and mature milk were collected in seven days (7d milk) and thirty days (30d milk) after delivery, respectively. Supplementation in the supplemented group was held after the collection of blood and 0h milk. The alpha-tocopherol analyzes were performed by high-performance liquid chromatography. Serum levels of alpha-tocopherol less than 516 μg/dL were considered indicative of nutritional deficiency. The average concentration of alphatocopherol in the serum of the control group mothers was 1159.8 ± 292.4 μg/dL and the supplemented group was 1128.3 ± 407.2 μg/dL (p = 0.281). All women had nutritional status in vitamin E suitable. In both groups, it was observed that the concentration of vitamin E in colostrum milk was higher compared to transitional and mature milk. In the supplemented group, the concentration of alpha-tocopherol in the milk increased 60 % after supplementation, from 1339.3 ± 414.2 μg/dL (0h milk) to 2234.7 ± 997.3 μg/dL (24h milk). While the control group values in colostrum 0h and colostrum 24h were similar (p = 0.681). In the control group the follow-on milk alphatocopherol value was 875.3 ± 292.4 μg/dL and in the group supplemented 1352.8 ± 542.3 μg/dL, an increase of 35% in the supplemented group compared to control (p <0.001). In mature milk alpha-tocopherol concentrations between the control group (426.6 ± 187.5 μg/dL) and supplemented (416.4 ± 214.2 μg/dL) were similar (p = 0.853). Only 24h milk supplemented group answered the nutritional requirement of alpha-tocopherol (4 mg/day) of the newborn. These results show that the transport of this micronutrient for milk occurs in a controlled and limited way. Thus, the native vitamin E supplementation increases the concentration of alpha-tocopherol in colostrum and milk and transition does not influence the concentration in mature milk. Only the increase in colostrum milk was sufficient to meet the nutritional requirement of premature newborns.

Análise wavelet e modelo de manchas em curvas de luz estelares dos telescópios espaciais Kepler e CoRoT

Analogous to sunspots and solar photospheric faculae, which visibility is modulated by stellar rotation, stellar active regions consist of cool spots and bright faculae caused by the magnetic field of the star. Such starspots are now well established as major tracers used to estimate the stellar rotation period, but their dynamic behavior may also be used to analyze other relevant phenomena such as the presence of magnetic activity and its cycles. To calculate the stellar rotation period, identify the presence of active regions and investigate if the star exhibits or not differential rotation, we apply two methods: a wavelet analysis and a spot model. The wavelet procedure is also applied here to study pulsation in order to identify specific signatures of this particular stellar variability for different types of pulsating variable stars. The wavelet transform has been used as a powerful tool for treating several problems in astrophysics. In this work, we show that the time-frequency analysis of stellar light curves using the wavelet transform is a practical tool for identifying rotation, magnetic activity, and pulsation signatures. We present the wavelet spectral composition and multiscale variations of the time series for four classes of stars: targets dominated by magnetic activity, stars with transiting planets, those with binary transits, and pulsating stars. We applied the Morlet wavelet (6th order), which offers high time and frequency resolution. By applying the wavelet transform to the signal, we obtain the wavelet local and global power spectra. The first is interpreted as energy distribution of the signal in time-frequency space, and the second is obtained by time integration of the local map. Since the wavelet transform is a useful mathematical tool for nonstationary signals, this technique applied to Kepler and CoRoT light curves allows us to clearly identify particular signatures for different phenomena. In particular, patterns were identified for the temporal evolution of the rotation period and other periodicity due to active regions affecting these light curves. In addition, a beat-pattern vii signature in the local wavelet map of pulsating stars over the entire time span was also detected. The second method is based on starspots detection during transits of an extrasolar planet orbiting its host star. As a planet eclipses its parent star, we can detect physical phenomena on the surface of the star. If a dark spot on the disk of the star is partially or totally eclipsed, the integrated stellar luminosity will increase slightly. By analyzing the transit light curve it is possible to infer the physical properties of starspots, such as size, intensity, position and temperature. By detecting the same spot on consecutive transits, it is possible to obtain additional information such as the stellar rotation period in the planetary transit latitude, differential rotation, and magnetic activity cycles. Transit observations of CoRoT-18 and Kepler-17 were used to implement this model.

Análise wavelet em curvas de luz estelares de sistemas binários da missão espacial CoRoT

Binary systems are key environments to study the fundamental properties of stars. In this work, we analyze 99 binary systems identified by the CoRoT space mission. From the study of the phase diagrams of these systems, our sample is divided into three groups: those whose systems are characterized by the variability relative to the binary eclipses; those presenting strong modulations probably due to the presence of stellar spots on the surface of star; and those whose systems have variability associated with the expansion and contraction of the surface layers. For eclipsing binary stars, phase diagrams are used to estimate the classification in regard to their morphology, based on the study of equipotential surfaces. In this context, to determine the rotation period, and to identify the presence of active regions, and to investigate if the star exhibits or not differential rotation and study stellar pulsation, we apply the wavelet procedure. The wavelet transform has been used as a powerful tool in the treatment of a large number of problems in astrophysics. Through the wavelet transform, one can perform an analysis in time-frequency light curves rich in details that contribute significantly to the study of phenomena associated with the rotation, the magnetic activity and stellar pulsations. In this work, we apply Morlet wavelet (6th order), which offers high time and frequency resolution and obtain local (energy distribution of the signal) and global (time integration of local map) wavelet power spectra. Using the wavelet analysis, we identify thirteen systems with periodicities related to the rotational modulation, besides the beating pattern signature in the local wavelet map of five pulsating stars over the entire time span.

Análise wavelet em curvas de luz estelares de sistemas binários da missão espacial CoRoT

Binary systems are key environments to study the fundamental properties of stars. In this work, we analyze 99 binary systems identified by the CoRoT space mission. From the study of the phase diagrams of these systems, our sample is divided into three groups: those whose systems are characterized by the variability relative to the binary eclipses; those presenting strong modulations probably due to the presence of stellar spots on the surface of star; and those whose systems have variability associated with the expansion and contraction of the surface layers. For eclipsing binary stars, phase diagrams are used to estimate the classification in regard to their morphology, based on the study of equipotential surfaces. In this context, to determine the rotation period, and to identify the presence of active regions, and to investigate if the star exhibits or not differential rotation and study stellar pulsation, we apply the wavelet procedure. The wavelet transform has been used as a powerful tool in the treatment of a large number of problems in astrophysics. Through the wavelet transform, one can perform an analysis in time-frequency light curves rich in details that contribute significantly to the study of phenomena associated with the rotation, the magnetic activity and stellar pulsations. In this work, we apply Morlet wavelet (6th order), which offers high time and frequency resolution and obtain local (energy distribution of the signal) and global (time integration of local map) wavelet power spectra. Using the wavelet analysis, we identify thirteen systems with periodicities related to the rotational modulation, besides the beating pattern signature in the local wavelet map of five pulsating stars over the entire time span.

Evolução dos sistemas de falhas de borda do Rifte Potiguar com base em curvas de crescimento de falhas

The discussion about rift evolution in the Brazilian Equatorial margin during the South America-Africa breakup in the Jurassic/Cretaceous has been focused in many researches. But rift evolution based on development and growth of faults has not been well explored. In this sense, we investigated the Cretaceous Potiguar Basin in the Equatorial margin of Brazil to understand the geometry of major faults and the influence of crustal heterogeneity and preexisting structural fabric in the evolution of the basin internal architecture. Previous studies pointed out that the rift is an asymmetrical half-graben elongated along the NE-SW direction. We used 2D seismic, well logs and 3D gravity modeling to analyze four major border fault segments and determine their maximum displacement (Dmax) and length (L) ratio in the Potiguar Rift. We constrained the 3D gravity modeling with well data and the interpretation of seismic sections. The difference of the fault displacement measured in the gravity model is in the order of 10% compared to seismic and well data. The fault-growth curves allowed us to divide the faulted rift border into four main fault segments, which provide roughly similar Dmax/L ratios. Fault-growth curves suggest that a regional uniform tectonic mechanism influenced growth of the rift fault segments. The variation of the displacements along the fault segments indicates that the fault segments were formed independently during rift initiation and were linked by hard and soft linkages. The latter formed relay ramps. In the interconnection zones the Dmax/L ratios are highest due to interference of fault segment motions. We divided the evolution of the Potiguar Rift into five stages based on these ratios and correlated them with the major tectonic stages of the breakup between South America and Africa in Early Cretaceous.

Evolução dos sistemas de falhas de borda do Rifte Potiguar com base em curvas de crescimento de falhas

The discussion about rift evolution in the Brazilian Equatorial margin during the South America-Africa breakup in the Jurassic/Cretaceous has been focused in many researches. But rift evolution based on development and growth of faults has not been well explored. In this sense, we investigated the Cretaceous Potiguar Basin in the Equatorial margin of Brazil to understand the geometry of major faults and the influence of crustal heterogeneity and preexisting structural fabric in the evolution of the basin internal architecture. Previous studies pointed out that the rift is an asymmetrical half-graben elongated along the NE-SW direction. We used 2D seismic, well logs and 3D gravity modeling to analyze four major border fault segments and determine their maximum displacement (Dmax) and length (L) ratio in the Potiguar Rift. We constrained the 3D gravity modeling with well data and the interpretation of seismic sections. The difference of the fault displacement measured in the gravity model is in the order of 10% compared to seismic and well data. The fault-growth curves allowed us to divide the faulted rift border into four main fault segments, which provide roughly similar Dmax/L ratios. Fault-growth curves suggest that a regional uniform tectonic mechanism influenced growth of the rift fault segments. The variation of the displacements along the fault segments indicates that the fault segments were formed independently during rift initiation and were linked by hard and soft linkages. The latter formed relay ramps. In the interconnection zones the Dmax/L ratios are highest due to interference of fault segment motions. We divided the evolution of the Potiguar Rift into five stages based on these ratios and correlated them with the major tectonic stages of the breakup between South America and Africa in Early Cretaceous.

Padrões de diversidade α (alfa) e β (beta) zooplanctônica em lagos tropicais: a importância da estrutura do habitat e da identidade das espécies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Padrões de diversidade α (alfa) e β (beta) zooplanctônica em lagos tropicais: a importância da estrutura do habitat e da identidade das espécies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Évaluation pharmacodynamique et sécurité d'emploi de l'Époétine alfa chez les patients aux soins intensifs

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Évaluation pharmacodynamique et sécurité d'emploi de l'Époétine alfa chez les patients aux soins intensifs

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Stable expression of a human-like sialylated recombinant thyrotropin in a chinese hamster ovary cell line expressing 'alfa'2,6-sialyltransferase

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

Studio del comportamento di poli-alfa-olefine come modificatori di viscosità negli oli lubrificanti

Il buon funzionamento di una qualsiasi tipologia di motore prevede l’utilizzo di un componente che abbia il compito di lubrificare le parti meccaniche in movimento, come, ad esempio, l’olio motore per l’automobile. Un fattore determinante nella scelta dell’olio è la variazione della sua viscosità in relazione alla variazione di temperatura, poiché la temperatura di esercizio di un macchinario è solitamente diversa dalla temperatura di avviamento. Tale valore viene identificato in maniera assoluta dal Viscosity Index (VI). L’olio motore è una formulazione complessa in cui sono presenti l’olio base ed una serie di additivi, tra cui molto importante è il modificatore di viscosità (Viscosity Index Improver, VII), che migliora il VI e permette di utilizzare lo stesso olio a basse ed alte temperature (olio multigrade). Come VII possono essere utilizzate diverse tipologie di polimeri solubili in olio, che variano per caratteristiche e target di mercato. La famiglia presa in esame in questa tesi è quella delle poli-alfa-olefine, utilizzate prevalentemente con oli base minerali, e più precisamente copolimeri etilene/propilene. Sono state analizzate le proprietà che questa famiglia ben nota di OCP (Olefin CoPolymer) ingenera nel sistema base-polimero. In particolare si è cercato di correlare le proprietà molecolari del polimero (composizione, peso molecolare e paracristallinità) con le proprietà “tecnologico-applicative” di ispessimento, stabilità meccanica al taglio, punto di non scorrimento, avviamento a freddo, pompabilità a freddo. L’attività è proseguita con la progettazione di un modello fisico, con l’obiettivo di predire il comportamento tecnologico del sistema olio-polimero in funzione delle proprietà molecolari di polimeri appartenenti alla classe delle poli-alfa-olefine lineari, esaminando anche le proprietà tecnologiche di un omopolimero sperimentale.

Curvas de Intensidad, Duración y Frecuencia en la Cuenca Nº68 Nicaragua

El clima es uno de los factores más e studiados a n ivel mundial y el más utilizado para la elaboración de planes de conservación de suelos y agua , construcción de obras hidráulicas que den un mejor uso y aprovechamiento de los recursos naturales. La construcción de C urvas de Intensidad – Duración – Frecuen cia como herramienta para la toma de decisión en el manejo, control y aprovechamiento del exceso de la precipitación es relevante para las zonas productivas y de escases de agua. El Objetivo de la investigación fue analizar el comportamiento de la s curvas IDF en la Cuenca N°68 con diferentes períodos de retorno de 5, 10, 15, 20 y 30 años con duraciones de 5, 10, 15, 30, 60 y 1 20 minutos. Se compararon dos modelos estadísticos Gumbel Tipo I y Aparicio 1997, ambos métodos permitieron es timar la intensidad de precipitación para los diferentes períodos de retorno. Para la selección de las estaciones pluviográficas se tomó como criterio las estaciones que proporcionaran la información necesaria para el periodo analizado 1975 - 1989 (Estación Aeropuerto Augusto C esa Sandino, Estación Tola, Estación Nandaime, Estación Masatepe Campos Azules). Al generar las curvas se presentaron algunos inconvenientes en la E stación Masatepe Campos A zules , esto fue ocasionado por posibles fallas en las estaciones pluviográficas como por ejemplo faltan de tinta en el pluviógrafo , cambio de operador, etc . El método de Gumbel Tipo I es el que nos brinda información más ajusta das a las condiciones del área de estudio ya que la prueba ajuste de bondad ajusto perfectamente los datos al mod elo estadístico mejorando los índices de probabilidad, en cambio el modelo estadístico Aparicio, 1997 sobre estima los valores de intensidad en los diferentes períodos de retornos, esto se observa al comparar los datos analizados con los datos calculados, los cuales presentan porcentaj es de sobrestimación del 7-54 %.