Measurement results of d18O, Mg/Ca, and Ti/Ca of sediment cores GeoB10042-1 and GeoB10043-3

The advection of relatively fresh Java Sea water through the Sunda Strait is presently responsible for the low-salinity "tongue" in the eastern tropical Indian Ocean with salinities as low as 32 per mil. The evolution of the hydrologic conditions in the eastern tropical Indian Ocean since the last glacial period, when the Sunda shelf was exposed and any advection via the Sunda Strait was cutoff, and the degree to which these conditions were affected by the Sunda Strait opening are not known. Here we have analyzed two sediment cores (GeoB 10042-1 and GeoB 10043-3) collected from the eastern tropical Indian Ocean off the Sunda Strait that cover the past ~40,000?years. We investigate the magnitude of terrigenous supply, sea surface temperature (SST), and seawater d18O (d18Osw) changes related to the sea level-driven opening of the Sunda Strait. Our new spliced records off the Sunda Strait show that during the last glacial, average SST was cooler and d18Osw was higher than elsewhere in the eastern tropical Indian Ocean. Seawater d18O decreased ~0.5 per mil after the opening of the Sunda Strait at ~10 kyr B.P. accompanied by an SST increase of 1.7°C. We suggest that fresher sea surface conditions have persisted ever since due to a continuous transport of low-salinity Java Sea water into the eastern tropical Indian Ocean via the Sunda Strait that additionally increased marine productivity through the concomitant increase in terrigenous supply.

A Frequency-Dependent Equivalence Between Groove Gap Waveguide and Rectangular Waveguide

Recently gap waveguides have been shown as a potential alternative to conventional waveguides in the millimeter-wave band. Groove Gap Waveguide (GGW) has until now been studied though direct correspondence with rectangular waveguide with the same propagation channel dimensions. However there have been observed differences in the above cutoff propagation characteristics between these waveguide types. Furthermore, the behaviour of GGW below cutoff remains unknown. This work presents a discussion of below and above cutoff propagation characteristics, and introduces a simple model that explains observed GGW behavior and establishes its propagation characteristics.

Autocriticismo, Estima Corporal e Sintomas de Perturbação do Comportamento Alimentar em Adolescentes do Sexo Feminino, Praticantes de Ballet e Andebol

Introdução: As Perturbações do Comportamento Alimentar (PCA) constituem um grave problema de saúde pública. Poucos estudos em Portugal ligam esta temática a áreas como o autocriticismo e a estima corporal. Assim, são nossos objetivos principais: explorar, numa amostra de adolescentes do sexo feminino, as diferenças entre praticantes de ballet e praticantes de andebol, nos sintomas de PCA, índice de massa corporal (IMC), dimensões avaliativas da aparência e níveis de autocriticismo; analisar se níveis maiores de autocriticismo e uma visão mais depreciativa em termos de aparência se associam a níveis mais elevados de sintomas de PCA (nas duas modalidades desportivas). Em virtude das associações encontradas, pretendemos realizar análises preditivas, controlando a influência de sintomas de depressão, ansiedade e stress. Metodologia: A amostra é constituída por 105 adolescentes do sexo feminino (n = 52; 49,5% do ballet e n = 53; 50,5% do andebol) com idades compreendidas entre os 12 e 18 anos (M = 14,5; DP = 1,80). As participantes preencheram um protocolo composto por um questionário sociodemográfico, pela Escala de Autocriticismo e Autotranquilização (FSCRS), pelo Teste de Atitudes Alimentares-25 (TAA-25/EAT-25), pela Escala Estima Corporal (BES) e pela Escala Depressão Ansiedade e Stress (DASS-21). Resultados: Verificaram-se percentagens preocupantes de eventual PCA (ponto de corte de 19) nas praticantes de Ballet (7,7%) e de Andebol (9,4%). Quanto ao IMC, na amostra de praticantes de ballet, encontrou-se uma percentagem relevante de jovens com magreza (34,6%). As praticantes de Ballet e de Andebol apenas se diferenciaram no IMC e na dimensão FSCRS_eu inadequado (valores superiores nas praticantes de Andebol). Verificaram-se, na subamostra Ballet, associações significativas entre a Motivação para a Magreza e as formas de autocriticismo FSCRS_eu inadequado, FSCRS_eu detestado, FSCRS_eu tranquilizador e FSCRS_total e entre os Comportamentos Bulímicos e as formas de autocriticismo FSCRS_eu detestado e FSCRS_total. Na subamostra Andebol constataram-se associações significativas entre a Motivação para a Magreza e a forma de autocriticismo FSCRS_eu inadequado e FSCRS_total. A dimensão FSCRS_eu detestado mostrou predizer, na subamostra Ballet, a Motivação para a Magreza e os Comportamentos Bulímicos. Na subamostra Andebol o BES_Peso foi o preditor significativo da Motivação para a Magreza. Discussão: É preocupante a percentagem de eventual PCA (em ambas em subamostras) bem como a percentagem de jovens que praticam Ballet com um IMC indicador de magreza, principalmente por serem jovens atletas e estarem mais focadas no seu corpo e forma física, estando mais vulneráveis ao desenvolvimento da patologia. É um contributo fundamental deste trabalho verificar associações (bem como o papel preditivo) nestas duas modalidades desportivas, separadamente, entre as formas de autocriticismo e as dimensões do TAA-25 Motivação para a Magreza e Comportamentos Bulímicos. Parece essencial o desenvolvimento de ações de sensibilização junto dos professores/treinadores, com o intuito de despertar uma maior atenção para a visão crítica das suas bailarinas/atletas em relação ao seu corpo, que parece influenciar as suas atitudes alimentares. Será importante iniciar estas ações/intervenções precocemente (antes mesmo da adolescência) não esquecendo a inclusão das figuras paternas, com vista a melhorar o seu sucesso, tendo consciência que particularmente no “nicho” desportivo do ballet a imagem/aparência e o peso continuam e continuarão, muito provavelmente, a ser valorizados e reforçados. / Introduction: Eating Disorders are a major public health problem. Few studies in Portugal associate this theme with areas such as self-criticism and body esteem. Thus, our main objectives are: to explore, in a sample of female adolescents, the differences between ballet and handball practitioners as to symptoms of eating disorders, body mass index (BMI) and evaluative dimensions of appearance and self-criticism levels; to analyze whether higher levels of self-criticism and a more derogatory vision in terms of appearance are associated with higher levels of PCA symptoms (in both sports). Having these associations into account, we intend to perform predictive analysis, controlling the influence of symptoms of depression, anxiety and stress. Methodology: Our sample is composed by 105 female adolescents (n = 52; 49.5% from ballet and n = 53; 50.5% from handball) with ages between 12 and 18 years (M = 14.5; DP = 1.80). The participants filled in a protocol composed by a sociodemographic questionnaire, the Forms of Self-Criticizing and Reassuring Scale (FSCRS), the Eating Attitudes Test-25 (TAA-25/EAT-25), the Body Esteem Scale (BES) and Depression, Anxiety and Stress Scale (DASS-21). Results: There were worrying percentages of eventual PCA (cutoff of 19) in Ballet practitioners (7.7%) and Handball (9.4%). As to the BMI, in the sample of practitioners of ballet we found a significant percentage of young people with malnutrition (34.6%). Ballet and Handball practitioners only differed in BMI and in the inadequate self form (higher values in Handball practitioners). In the Ballet subsample there were significant associations between Motivation for thinness and forms of self-criticism, inadequate self form, hated self form, reassure self form and total self criticism and between Bulimic behaviors and inadequate self form and total self criticism. In the Handball subsample, significant associations were found between Motivation for thinness, the inadequate self form and total self criticism. The hated self form predicted, in the Ballet subsample, Motivation for thinness and Bulimic behaviors. In the subsample Handball BES_Weight was the significant predictor of Motivation for thinness. Discussion: The percentage of any Eating Disorders (in both subsamples) and the percentage of young people who practice ballet with a IMC indicating thinness is worrying, especially in young athletes who are more focused on their body and physical form, being more vulnerable to develop these disorders/symptoms. A major contribution of this work is to have shown the associations (as well as the predictive role), in these two sports, separately, between self-criticism forms and the TAA-25 dimensions Motivation for thinness and Bulimic behaviors. It seems essential to develop awareness-raising among teachers/trainers, in order to raise greater attention to the critical view of their dancers / athletes in relation to their body, which seems to influence their eating attitudes. It will be important to start these actions/interventions earlier (even before adolescence) not forgetting the inclusion of parents in order to improve their success, particularly in the ballet “niche”, where image/appearance and weight will most likely continue to be valued and reinforced.

Design and modeling of optical fibers for spatial division multiplexing using the orbital angular momentum of light

Les besoins toujours croissants en terme de transfert de données numériques poussent au développement de nouvelles technologies pour accroître la capacité des réseaux, notamment en ce qui concerne les réseaux de fibre optique. Parmi ces nouvelles technologies, le multiplexage spatial permet de multiplier la capacité des liens optiques actuels. Nous nous intéressons particulièrement à une forme de multiplexage spatial utilisant le moment cinétique orbital de la lumière comme base orthogonale pour séparer un certain nombre de canaux. Nous présentons d’abord les notions d’électromagnétisme et de physique nécessaires à la compréhension des développements ultérieurs. Les équations de Maxwell sont dérivées afin d’expliquer les modes scalaires et vectoriels de la fibre optique. Nous présentons également d’autres propriétés modales, soit la coupure des modes, et les indices de groupe et de dispersion. La notion de moment cinétique orbital est ensuite introduite, avec plus particulièrement ses applications dans le domaine des télécommunications. Dans une seconde partie, nous proposons la carte modale comme un outil pour aider au design des fibres optiques à quelques modes. Nous développons la solution vectorielle des équations de coupure des modes pour les fibres en anneau, puis nous généralisons ces équations pour tous les profils de fibres à trois couches. Enfin, nous donnons quelques exemples d’application de la carte modale. Dans la troisième partie, nous présentons des designs de fibres pour la transmission des modes avec un moment cinétique orbital. Les outils développés dans la seconde partie sont utilisés pour effectuer ces designs. Un premier design de fibre, caractérisé par un centre creux, est étudié et démontré. Puis un second design, une famille de fibres avec un profil en anneau, est étudié. Des mesures d’indice effectif et d’indice de groupe sont effectuées sur ces fibres. Les outils et les fibres développés auront permis une meilleure compréhension de la transmission dans la fibre optique des modes ayant un moment cinétique orbital. Nous espérons que ces avancements aideront à développer prochainement des systèmes de communications performants utilisant le multiplexage spatial.

Avaliação breve do défice executivo em pessoas idosas com Acidente Vascular Cerebral: Validação da Bateria de Avaliação Frontal

RESUMO Objetivos: O Acidente Vascular Cerebral (AVC) potencia o desenvolvimento de disfunção executiva, conduzindo a défice no desempenho das tarefas do quotidiano. A avaliação neuropsicológica das funções executivas é importante para desenvolver estratégias de reabilitação adequadas. Assim, são objetivos descrever os dados normativos, precisão de diagnóstico, propriedades psicométricas e análise fatorial da Bateria de Avaliação Frontal (FAB), instrumento breve e de rápida administração, numa amostra de idosos com AVC. Métodos: Inserida no projeto Trajetórias do Envelhecimento de Idosos em Resposta Social, esta investigação conta com uma amostra de 112 pessoas idosas com diagnóstico médico de AVC e 157 pessoas idosas de um subgrupo de controlo sem AVC. Os sujeitos apresentam idades compreendidas entre os 60 e os 100 anos (M = 78,20; DP = 7,57) sendo maioritariamente do sexo feminino (n = 194). A avaliação inclui entrevistas e testes neuropsicológicos agrupados em medidas de funcionamento executivo, medidas cognitivas de referência e medidas clínicas de controlo. Resultados: As variáveis idade e escolaridade interferiram nas pontuações obtidas na amostra clínica, não sendo verificado impacto da variável sexo. Para um ponto de corte de 7, a FAB teve uma sensibilidade de 83,4% e especificidade de 66,1 % (AUC = 0,64); revelou um alfa de Cronbach de 0,79 e correlações fortes com os testes executivos (teste de Stroop, Figura Complexa de Rey, fator Atencional-Executivo do Montreal Cognitive Assessment e Alternância nos testes de Fluência verbal). A análise fatorial confirmatória apontou uma estrutura com um fator. Conclusões: A FAB apresenta boa consistência interna, validade convergente e validade de constructo, aparentando ser uma escala útil para avaliar o défice executivo em pessoas idosas com AVC. Dadas algumas limitações do estudo, que poderão explicar a fraca precisão diagnóstica da FAB, são incentivadas investigações futuras pois a FAB revelou-se um instrumento com propriedades psicométricas promissoras. ABSTRACT Goals: Stroke potentiates the development of executive dysfunction, leading to impairment in performance of daily activities. The neuropsychological assessment of executive functions is important to develop adequate rehabilitation strategies. Thus, describing the normative data, diagnostic accuracy, psychometric properties and factor analysis of the Frontal Assessment Battery (FAB), a brief and easy to administer instrument, in a clinical sample with stroke are objectives of this study. Methods: Being part of the Aging Trajectories of Institutionalized Elderly, this research has a sample 112 elderly people with a medical diagnosis of stroke and a control subgroup of 157 elderly people. The subjects have ages between 60 and 100 years old (M = 78.20, SD = 7.57), mostly females (n = 194). The measurements used include interviews and neuropsychological tests grouped in executive functioning measures, cognitive measures of reference and clinical measures of control. Results: The variables age and education affect the scores obtained in the clinical subgroup, having the variable gender no impact on these. Using a cutoff score of 7, the FAB had a sensitivity of 83.4% and a specificity of 66.1% for screening stroke (AUC = 0.64); showed a Cronbach's α of 0.79, and strong correlations with executive tests (Stroop test, Rey Complex Figure, Attentional-Executive factor of Montreal Cognitive Assessment and Switching in the verbal fluency tests). The confirmatory factor analysis supported a one-factor structure. Conclusions: The FAB presents good internal consistency, convergent, and construct when used for elderly with stroke. Due to some limitations of the study, which may explain the weak discriminant validity, further investigations are encouraged because FAB has showed promising psychometric properties.

MRI-based assessment of the pineal gland in a large population of children aged 0-5 years and comparison with pineoblastoma: part I, the solid gland.

INTRODUCTION: Differentiation between normal solid (non-cystic) pineal glands and pineal pathologies on brain MRI is difficult. The aim of this study was to assess the size of the solid pineal gland in children (0-5 years) and compare the findings with published pineoblastoma cases. METHODS: We retrospectively analyzed the size (width, height, planimetric area) of solid pineal glands in 184 non-retinoblastoma patients (73 female, 111 male) aged 0-5 years on MRI. The effect of age and gender on gland size was evaluated. Linear regression analysis was performed to analyze the relation between size and age. Ninety-nine percent prediction intervals around the mean were added to construct a normal size range per age, with the upper bound of the predictive interval as the parameter of interest as a cutoff for normalcy. RESULTS: There was no significant interaction of gender and age for all the three pineal gland parameters (width, height, and area). Linear regression analysis gave 99 % upper prediction bounds of 7.9, 4.8, and 25.4 mm(2), respectively, for width, height, and area. The slopes (size increase per month) of each parameter were 0.046, 0.023, and 0.202, respectively. Ninety-three percent (95 % CI 66-100 %) of asymptomatic solid pineoblastomas were larger in size than the 99 % upper bound. CONCLUSION: This study establishes norms for solid pineal gland size in non-retinoblastoma children aged 0-5 years. Knowledge of the size of the normal pineal gland is helpful for detection of pineal gland abnormalities, particularly pineoblastoma.

Hexagonal patterns in finite domains

In many mathematical models for pattern formation, a regular hexagonal pattern is stable in an infinite region. However, laboratory and numerical experiments are carried out in finite domains, and this imposes certain constraints on the possible patterns. In finite rectangular domains, it is shown that a regular hexagonal pattern cannot occur if the aspect ratio is rational. In practice, it is found experimentally that in a rectangular region, patterns of irregular hexagons are often observed. This work analyses the geometry and dynamics of irregular hexagonal patterns. These patterns occur in two different symmetry types, either with a reflection symmetry, involving two wavenumbers, or without symmetry, involving three different wavenumbers. The relevant amplitude equations are studied to investigate the detailed bifurcation structure in each case. It is shown that hexagonal patterns can bifurcate subcritically either from the trivial solution or from a pattern of rolls. Numerical simulations of a model partial differential equation are also presented to illustrate the behaviour.

The Askaryan radio array

The Askar'yan Radio Array (ARA), a neutrino detector to be situated at the South Pole next to the IceCube detector, will be sensitive to ultrahigh-energy cosmic neutrinos above 0.1 EeV and will have the greatest sensitivity within the favored energy range from 0.1 EeV up to 10 EeV. Neutrinos of this energy are guaranteed by current observations of the GZK-cutoff by the HiRes and Pierre Auger Observatories. The detection method is based on Cherenkov emission by a neutrino induced cascade in the ice, coherent at radio wavelengths, which was predicted by Askar'yan in 1962 and verified in beam tests at SLAC in 2006. The detector is planned to consist of 37 stations with 16 antennas each, deployed at depths of up to 200 m under the ice surface. During the last two polar seasons (2010-2011, 2011-2012), a prototype station and a first detector station were successfully deployed and are taking data. These data have been and are currently being analyzed to study the ambient noise background and the radio frequency properties of the South Pole ice sheet. A worldwide collaboration is working on the planning, construction and data analysis of the detector array. This article will give a short report on the status of the ARA detector and show recent results from the recorded data. © 2013 AIP Publishing LLC.

Analysis of Molecular Dynamics Simulations of Protein Folding

Microsecond long Molecular Dynamics (MD) trajectories of biomolecular processes are now possible due to advances in computer technology. Soon, trajectories long enough to probe dynamics over many milliseconds will become available. Since these timescales match the physiological timescales over which many small proteins fold, all atom MD simulations of protein folding are now becoming popular. To distill features of such large folding trajectories, we must develop methods that can both compress trajectory data to enable visualization, and that can yield themselves to further analysis, such as the finding of collective coordinates and reduction of the dynamics. Conventionally, clustering has been the most popular MD trajectory analysis technique, followed by principal component analysis (PCA). Simple clustering used in MD trajectory analysis suffers from various serious drawbacks, namely, (i) it is not data driven, (ii) it is unstable to noise and change in cutoff parameters, and (iii) since it does not take into account interrelationships amongst data points, the separation of data into clusters can often be artificial. Usually, partitions generated by clustering techniques are validated visually, but such validation is not possible for MD trajectories of protein folding, as the underlying structural transitions are not well understood. Rigorous cluster validation techniques may be adapted, but it is more crucial to reduce the dimensions in which MD trajectories reside, while still preserving their salient features. PCA has often been used for dimension reduction and while it is computationally inexpensive, being a linear method, it does not achieve good data compression. In this thesis, I propose a different method, a nonmetric multidimensional scaling (nMDS) technique, which achieves superior data compression by virtue of being nonlinear, and also provides a clear insight into the structural processes underlying MD trajectories. I illustrate the capabilities of nMDS by analyzing three complete villin headpiece folding and six norleucine mutant (NLE) folding trajectories simulated by Freddolino and Schulten [1]. Using these trajectories, I make comparisons between nMDS, PCA and clustering to demonstrate the superiority of nMDS. The three villin headpiece trajectories showed great structural heterogeneity. Apart from a few trivial features like early formation of secondary structure, no commonalities between trajectories were found. There were no units of residues or atoms found moving in concert across the trajectories. A flipping transition, corresponding to the flipping of helix 1 relative to the plane formed by helices 2 and 3 was observed towards the end of the folding process in all trajectories, when nearly all native contacts had been formed. However, the transition occurred through a different series of steps in all trajectories, indicating that it may not be a common transition in villin folding. The trajectories showed competition between local structure formation/hydrophobic collapse and global structure formation in all trajectories. Our analysis on the NLE trajectories confirms the notion that a tight hydrophobic core inhibits correct 3-D rearrangement. Only one of the six NLE trajectories folded, and it showed no flipping transition. All the other trajectories get trapped in hydrophobically collapsed states. The NLE residues were found to be buried deeply into the core, compared to the corresponding lysines in the villin headpiece, thereby making the core tighter and harder to undo for 3-D rearrangement. Our results suggest that the NLE may not be a fast folder as experiments suggest. The tightness of the hydrophobic core may be a very important factor in the folding of larger proteins. It is likely that chaperones like GroEL act to undo the tight hydrophobic core of proteins, after most secondary structure elements have been formed, so that global rearrangement is easier. I conclude by presenting facts about chaperone-protein complexes and propose further directions for the study of protein folding.

Montreal Cognitive Assessment (MoCA): validation study for vascular dementia

The Montreal Cognitive Assessment (MoCA) is a brief instrument developed for the screening of milder forms of cognitive impairment, having surpassed the well-known limitations of the MMSE. The aim of the present study was to validate the MoCA as well as its short version, which was proposed by the NINDS-CSN VCI Harmonization Standards for screening Vascular Dementia (VaD) patients. The results, based on a homogeneous sample of 34 VaD patients, indicate that the MoCA is a psychometrically valid and reliable instrument for cognitive screening in VaD patients, showing excellent discriminant validity. Both the full and short versions of the MoCA had excellent diagnostic accuracy in discriminating VaD patients, exhibiting an area under curve (AUC) higher than the MMSE [AUC(MoCA full version) = .950; 95% IC = .868-.988; AUC(MoCA short version) = .936; 95% IC = .849-.981; AUC(MMSE) = .860; 95% IC = .754-.932]. With a cutoff below 17 on the MoCA full version and 8 on the short version, the results for sensitivity, specificity, positive and negative predictive values, and classification accuracy were superior compared to the MMSE. In conclusion, both versions of the MoCA are valid, reliable, sensitive and accurate screening instruments for VaD patients.

Antimony-based type-II superlattice infrared detectors

Numerous applications within the mid- and long-wavelength infrared are driving the search for efficient and cost effective detection technologies in this regime. Theoretical calculations have predicted high performance for InAs/GaSb type-II superlattice structures, which rely on mature growth of III-V semiconductors and offer many levels of freedom in design due to band structure engineering. This work focuses on the fabrication and characterization of type-II superlattice infrared detectors. Standard UV-based photolithography was used combined with chemical wet or dry etching techniques in order to fabricate antinomy-based type-II superlattice infrared detectors. Subsequently, Fourier transform infrared spectroscopy and radiometric techniques were applied for optical characterization in order to obtain a detector's spectrum and response, as well as the overall detectivity in combination with electrical characterization. Temperature dependent electrical characterization was used to extract information about the limiting dark current processes. This work resulted in the first demonstration of an InAs/GaSb type-II superlattice infrared photodetector grown by metalorganic chemical vapor deposition. A peak detectivity of 1.6x10^9 Jones at 78 K was achieved for this device with a 11 micrometer zero cutoff wavelength. Furthermore the interband tunneling detector designed for the mid-wavelength infrared regime was studied. Similar results to those previously published were obtained.

Airborne remote sensing of ocean wave directional wavenumber spectra in the marginal ice zone

Interactions between surface waves and sea ice are thought to be an important, but poorly understood, physical process in the atmosphere-ice-ocean system. In this work, airborne scanning lidar was used to observe ocean waves propagating into the marginal ice zone (MIZ). These represent the first direct spatial measurements of the surface wave field in the polar MIZ. Data were compared against two attenuation models, one based on viscous dissipation and one based on scattering. Both models were capable of reproducing the measured wave energy. The observed wavenumber dependence of attenuation was found to be consistent with viscous processes, while the spectral spreading of higher wavenumbers suggested a scattering mechanism. Both models reproduced a change in peak direction due to preferential directional filtering. Floe sizes were recorded using co-located visible imagery, and their distribution was found to be consistent with ice breakup by the wave field.

Influência do estado nutricional materno em vitamina A sobre os níveis de imunoglobulina A no colostro humano

Mothers with good vitamin A nutritional status during gestation and lactation are better able to nourish and protect their infant with maternal milk. Our hypothesis is that women with more serum retinol have more retinol and secretory immunoglobulin A in colostrum. 190 healthy puerperal women from a Brazilian public maternity were recruited and divided according to the cutoff point for serum retinol (30 μg/dL). A number of the women was supplemented with 200000 UI (60 mg) of retinyl palmitate in the immediate postpartum. Serum and colostrum were collected on the 1st day postpartum and colostrum again on the following day. Retinol (serum and colostrum) was analyzed by HPLC and SIgA (colostrum) by turbidimetry. The mothers presented with adequate biochemical indicators of nutritional status, according to serum retinol (44.6 μg/dL). There were significant differences (p= 0.0017 and p= 0.043, respectively) in retinol and SIgA levels in the colostrum of mothers with serum retinol > 30 μg/dL and < 30 μg/dL. The concentration of SIgA in the colostrum of non-supplemented mothers on the 1st day postpartum was 822.6 mg/dL, decreasing after 24 hours to 343.7 mg/dL. Supplemented mothers showed levels of SIgA in colostrum of 498.9 mg/dL on the 2nd day postpartum (p= 0.00006). The colostrum of women with good vitamin A nutritional status had more retinol and SIgA. Additionally, maternal supplementation increases the levels of SIgA in colostrum. The higher levels of SIgA on the 1st day postpartum showed the importance of early breastfeeding, given that it provides considerable immunological benefits to newborn infants

Efeito do estado nutricional bioquímico de retinol e alfatocoferol sobre seus níveis em lactantes

Vitamins A and E are essential nutrients in many biological processes, so that their adequate supply to the neonate is crucial. However, the bioavailability of vitamins may be limited by factors such as maternal nutritional status and the interaction between nutrients. This study aimed to investigate the effect of biochemical nutritional status of retinol and alpha-tocopherol levels in serum and colostrum. The study included 103 healthy puerperal women treated at the reference state maternity hospital (Natal-RN). Colostrum and serum samples were collected fasting in the immediate postpartum period and the analysis of retinol and alpha-tocopherol were determined by high-performance liquid chromatography. Specific cutoff points were adopted to characterize the biochemical status of vitamins A and E. For the total group of lactanting women the average concentration of retinol in serum (1.49 ± 0.4 μmol/L-1) and colostrum (2.18 ± 0.8 μmol/L-1), as well as alpha-tocopherol in serum (26.4 ± 8.0 μmol/L-1) and colostrum (26.1 ± 12.8 μmol/L-1), indicated adequate biochemical state. However, when evaluating the individual, was found a high prevalence of deficient serum (15%) and colostrum retinol (50%), and also alphatocopherol in serum (16%) and colostrum (61%). In women with serum retinol ≥ 1.05 μmol/L-1, found an inverse correlation between serum retinol and alpha-tocopherol in colostrum (p = 0.008, r = -0.28). This association was not observed in women with serum retinol <1.05 μmol/L-1. This situation demonstrates for the first time in humans that high physiological levels of serum retinol, without supplementation, can negatively influence the transfer of alpha-tocopherol in breast milk. Although the diagnosis of satisfactory nutritional status lactanting women showed high risk of subclinical deficiency of vitamins A and E from measurements made in the colostrum

Multicenter prospective validation of the Baveno IV and Baveno II/III criteria in cirrhosis patients with variceal bleeding

International audience