Relative importance of female-specific and non-female-specific effects on variation in iron stores between women

Women have lower iron stores than men because of iron loss during their reproductive years. However, variation between women could result from differences in iron loss, aspects of iron homeostasis common to men and women, or a combination of both. We compared the effects of age, menopause, menstrual blood loss and the number of pregnancies (sex-specific factors), and the effects of genetic variation, on markers of iron stores. We assessed how much the same genes or other familial factors influence iron status in both men and women. Data from 2039 female twins who participated in studies of reproductive health and iron status were used to estimate the proportions of variation that could be ascribed to genes, environment and measured factors. Significant effects of age, menopausal status and magnitude of menstrual blood loss were demonstrated, accounting for up to 18% of variance in serum ferritin in this sample, but number of children had no significant effect. Genetic effects were more than twice as great as sex-specific effects. The within-pair similarity of ferritin values in dizygotic female twin pairs was greater than for dizygotic opposite-sex pairs, but this difference was not quite significant, consistent with a minor role for sex-specific factors; and the opposite-sex within-pair differences did not diminish significantly with age. We conclude that the contribution of genetic differences between women to variation in iron stores outweighs the comparatively small effects of interindividual variation in iron loss through variation in menstruation and number of pregnancies.

Real-time 3D interactive segmentation of echocardiographic data through user-based deformation of B-spline explicit active surfaces

Image segmentation is an ubiquitous task in medical image analysis, which is required to estimate morphological or functional properties of given anatomical targets. While automatic processing is highly desirable, image segmentation remains to date a supervised process in daily clinical practice. Indeed, challenging data often requires user interaction to capture the required level of anatomical detail. To optimize the analysis of 3D images, the user should be able to efficiently interact with the result of any segmentation algorithm to correct any possible disagreement. Building on a previously developed real-time 3D segmentation algorithm, we propose in the present work an extension towards an interactive application where user information can be used online to steer the segmentation result. This enables a synergistic collaboration between the operator and the underlying segmentation algorithm, thus contributing to higher segmentation accuracy, while keeping total analysis time competitive. To this end, we formalize the user interaction paradigm using a geometrical approach, where the user input is mapped to a non-cartesian space while this information is used to drive the boundary towards the position provided by the user. Additionally, we propose a shape regularization term which improves the interaction with the segmented surface, thereby making the interactive segmentation process less cumbersome. The resulting algorithm offers competitive performance both in terms of segmentation accuracy, as well as in terms of total analysis time. This contributes to a more efficient use of the existing segmentation tools in daily clinical practice. Furthermore, it compares favorably to state-of-the-art interactive segmentation software based on a 3D livewire-based algorithm.

Mortality among patients with non-affective functional psychoses in a metropolitan area of South-Eastern Brazil

High mortality rates among those suffering from schizophrenia and related psychoses have been consistently described in developed societies. However, to date there is a lack of data on this matter in Brazil. In order to examine this issue, a prospective 2-year follow-up study was carried out in S. Paulo. The sample consisted of 120 consecutive admissions to psychiatric hospitals in a defined catchment area, aged 18 to 44 years old, with clinical diagnoses of non-affective functional psychoses according to the ICD-9. After 2 years, 116 (96.7%) subjects were traced. During the study period there were 7 deaths (6.0% of those traced), 5 (4.3%) due to suicide. All but one of the suicides occurred in the first year after discharge from hospital. Age and sex Standardised Mortality Ratios (relative to rates for the population of the city of Sao Paulo) were 8.4 for overall mortality (95% confidence interval: 4.0-15.9) and 317.9 for deaths due to suicide (95% confidence interval: 125.2-668.3). These results are in agreement with previous studies, and show that in Brazil non-affective functional psychoses are life-threatening illnesses, which need adequate care, particularly when patients go back to live in the community after hospital discharge.

Response of a multi-domain continental margin to compression: Study from seismic reflection-refraction and numerical modelling in the Tagus Abyssal Plain

The effects of the Miocene through Present compression in the Tagus Abyssal Plain are mapped using the most up to date available to scientific community multi-channel seismic reflection and refraction data. Correlation of the rift basin fault pattern with the deep crustal structure is presented along seismic line IAM-5. Four structural domains were recognized. In the oceanic realm mild deformation concentrates in Domain I adjacent to the Tore-Madeira Rise. Domain 2 is characterized by the absence of shortening structures, except near the ocean-continent transition (OCT), implying that Miocene deformation did not propagate into the Abyssal Plain, In Domain 3 we distinguish three sub-domains: Sub-domain 3A which coincides with the OCT, Sub-domain 3B which is a highly deformed adjacent continental segment, and Sub-domain 3C. The Miocene tectonic inversion is mainly accommodated in Domain 3 by oceanwards directed thrusting at the ocean-continent transition and continentwards on the continental slope. Domain 4 corresponds to the non-rifted continental margin where only minor extensional and shortening deformation structures are observed. Finite element numerical models address the response of the various domains to the Miocene compression, emphasizing the long-wavelength differential vertical movements and the role of possible rheologic contrasts. The concentration of the Miocene deformation in the transitional zone (TC), which is the addition of Sub-domain 3A and part of 3B, is a result of two main factors: (1) focusing of compression in an already stressed region due to plate curvature and sediment loading; and (2) theological weakening. We estimate that the frictional strength in the TC is reduced in 30% relative to the surrounding regions. A model of compressive deformation propagation by means of horizontal impingement of the middle continental crust rift wedge and horizontal shearing on serpentinized mantle in the oceanic realm is presented. This model is consistent with both the geological interpretation of seismic data and the results of numerical modelling.

A non-pixel image reader for continuous image detection based on tandem heterostructures

An optically addressed read-write sensor based on two stacked p-i-n heterojunctions is analyzed. The device is a two terminal image sensing structure. The charge packets are injected optically into the p-i-n writer and confined at the illuminated regions changing locally the electrical field profile across the p-i-n reader. An optical scanner is used for charge readout. The design allows a continuous readout without the need for pixel-level patterning. The role of light pattern and scanner wavelengths on the readout parameters is analyzed. The optical-to-electrical transfer characteristics show high quantum efficiency, broad spectral response, and reciprocity between light and image signal. A numerical simulation supports the imaging process. A black and white image is acquired with a resolution around 20 mum showing the potentiality of these devices for imaging applications.

Stacked photo-sensing devices based on SiC alloys A non-pixelled architecture for imagers and demultiplexing devices

In this review paper different designs based on stacked p-i'-n-p-i-n heterojunctions are presented and compared with the single p-i-n sensing structures. The imagers utilise self-field induced depletion layers for light detection and a modulated laser beam for sequential readout. The effect of the sensing element structure, cell configurations (single or tandem), and light source properties (intensity and wavelength) are correlated with the sensor output characteristics (light-to-dark sensivity, spatial resolution, linearity and S/N ratio). The readout frequency is optimized showing that scans speeds up to 104 lines per second can be achieved without degradation in the resolution. Multilayered p-i'-n-p-i-n heterostructures can also be used as wavelength-division multiplexing /demultiplexing devices in the visible range. Here the sensor element faces the modulated light from different input colour channels, each one with a specific wavelength and bit rate. By reading out the photocurrent at appropriated applied bias, the information is multiplexed or demultiplexed and can be transmitted or recovered again. Electrical models are present to support the sensing methodologies.

Predicting the revolving door phenomenon among patients with schizophrenic, affective disorders and non-organic psychoses

OBJECTIVE: The aim of the study was to identify the variables that predict the revolving door phenomenon in psychiatric hospital at the moment of a second admission. METHODS: The sample consisted of 3,093 patients who have been followed during 5 to 24 years after their first hospital admission due to schizophrenia, and affective or psychotic disorders. Those who had had four or more admissions during the study period were considered as revolving door patients. Logistic regression analyses were used to assess the impact of gender, age, marital status, urban conditions, diagnosis, mean period of stay on the first admission, interval between the first and second admissions on the patterns of hospitalization. RESULTS: The variables with the highest predictive power for readmission were the interval between first and second admissions, and the length of stay in the first admission. CONCLUSIONS: These data may help public health planners in providing optimal care to a small group of patients with more effective utilization of the available services.

Identificação das categorias mais relevantes da classificação internacional de funcionalidade, incapacidade e saúde para os terapeutas ocupacionais que exercem funções em unidades de cuidados continuados integrados

As constantes alterações das realidades sociais e epidemiológicas em associação ao envelhecimento populacional conduziram a insuficiências dos Sistemas Social e de Saúde que requerem uma reestruturação ao nível da adequação dos cuidados de saúde a prestar, pelo que, em resposta a esta necessidade foi criada a Rede Nacional de Cuidados Continuados Integrados. O presente estudo, de natureza qualitativa e carácter exploratório, tem como objectivo compreender a percepção dos Terapeutas Ocupacionais que trabalham em Unidades de Cuidados Continuados Integrados relativamente às categorias que considerem mais relevantes da Classificação Internacional da Funcionalidade, Incapacidade e Saúde, tendo sido aplicada uma entrevista a 8 profissionais a exercer funções em Unidades da Zona Norte, resultante de um processo de amostragem não probabilística e de conveniência. Como método de recolha de dados foi aplicada uma entrevista semi-estruturada, cujo guião foi construído após revisão bibliográfica, tendo por base as categorias definidas pelo modelo da Classificação Internacional da Funcionalidade, Incapacidade e Saúde e, posteriormente, analisado por um painel de peritos, tendo-se procedido à realização de uma entrevista piloto a um elemento, sem que esta contasse para a análise. A partir da análise das entrevistas realizadas procedemos à identificação das unidades de significado, tendo os conceitos sido ligados às categorias da Classificação que o representam de uma forma mais adequada, de acordo com as linking rules, tendo sido identificadas as categorias mais relevantes para os Terapeutas Ocupacionais a exercer funções em Unidades de Cuidados Continuados Integrados. Com a realização deste estudo, que pretende ser um primeiro passo para a criação de um futuro Core Set em Cuidados Continuados, foi-nos possível verificar que o maior número de categorias foram observadas no componente Actividades e Participação, tendo sido contabilizadas 70 (40,7%). Por outro lado, o componente Estruturas do corpo é o que integra menor número, contando com 19 categorias (11,05%). Assim, pensamos que a criação de um Core Set em Cuidados Continuados poderá beneficiar e facilitar a comunicação entre os profissionais destas equipas. No entanto, é importante ressalvar que a terminologia desta Classificação deverá ser utilizada de uma forma concertada com a linguagem específica da Terapia Ocupacional. Palavras-chave: Classificação Internacional da Funcionalidade, Incapacidade e Saúde, Core Set, Terapeutas Ocupacionais, Unidades de Cuidados Continuados Integrados.

Data mining contributions to characterize MV consumers and to improve the suppliers-consumers settlements

This paper deals with the establishment of a characterization methodology of electric power profiles of medium voltage (MV) consumers. The characterization is supported on the data base knowledge discovery process (KDD). Data Mining techniques are used with the purpose of obtaining typical load profiles of MV customers and specific knowledge of their customers’ consumption habits. In order to form the different customers’ classes and to find a set of representative consumption patterns, a hierarchical clustering algorithm and a clustering ensemble combination approach (WEACS) are used. Taking into account the typical consumption profile of the class to which the customers belong, new tariff options were defined and new energy coefficients prices were proposed. Finally, and with the results obtained, the consequences that these will have in the interaction between customer and electric power suppliers are analyzed.

Data mining techniques contributions to support electrical vehicle demand response

The introduction of Electric Vehicles (EVs) together with the implementation of smart grids will raise new challenges to power system operators. This paper proposes a demand response program for electric vehicle users which provides the network operator with another useful resource that consists in reducing vehicles charging necessities. This demand response program enables vehicle users to get some profit by agreeing to reduce their travel necessities and minimum battery level requirements on a given period. To support network operator actions, the amount of demand response usage can be estimated using data mining techniques applied to a database containing a large set of operation scenarios. The paper includes a case study based on simulated operation scenarios that consider different operation conditions, e.g. available renewable generation, and considering a diversity of distributed resources and electric vehicles with vehicle-to-grid capacity and demand response capacity in a 33 bus distribution network.

A model updating technique based on FRFs for damped structures

Model updating methods often neglect that in fact all physical structures are damped. Such simplification relies on the structural modelling approach, although it compromises the accuracy of the predictions of the structural dynamic behaviour. In the present work, the authors address the problem of finite element (FE) model updating based on measured frequency response functions (FRFs), considering damping. The proposed procedure is based upon the complex experimental data, which contains information related to the damped FE model parameters and presents the advantage of requiring no prior knowledge about the damping matrix structure or its content, only demanding the definition of the damping type. Numerical simulations are performed in order to establish the applicability of the proposed damped FE model updating technique and its results are discussed in terms of the correlation between the simulated experimental complex FRFs and the ones obtained from the updated FE model.

Chemical and biological studies from an Azorean macroalga: Ulva rigida

3rd Portuguese Meeting on Medicinal Chemistry and 1st Portuguese-Spanish-Brazilian Meeting on Medicinal Chemistry, Aveiro, 28-30 Novembro 2012.

The effects of air pollution on cardiovascular diseases: lag structures

OBJECTIVE: To assess the lag structure between air pollution exposure and elderly cardiovascular diseases hospital admissions, by gender. METHODS: Health data of people aged 64 years or older was stratified by gender in São Paulo city, Southeastern Brazil, from 1996 to 2001. Daily levels of air pollutants (CO, PM10, O3, NO2, and SO2) , minimum temperature, and relative humidity were also analyzed. It were fitted generalized additive Poisson regressions and used constrained distributed lag models adjusted for long time trend, weekdays, weather and holidays to assess the lagged effects of air pollutants on hospital admissions up to 20 days after exposure. RESULTS: Interquartile range increases in PM10 (26.21 mug/m³) and SO2 (10.73 mug/m³) were associated with 3.17% (95% CI: 2.09-4.25) increase in congestive heart failure and 0.89% (95% CI: 0.18-1.61) increase in total cardiovascular diseases at lag 0, respectively. Effects were higher among female group for most of the analyzed outcomes. Effects of air pollutants for different outcomes and gender groups were predominately acute and some "harvesting" were found. CONLUSIONS: The results show that cardiovascular diseases in São Paulo are strongly affected by air pollution.

a-SiH p-i-n structures with extreme i-layer thickness

We present measurements and numerical simulation of a-Si:H p-i-n detectors with a wide range of intrinsic layer thickness between 2 and 10 pm. Such a large active layer thickness is required in applications like elementary particle detectors or X-ray detectors. For large thickness and depending on the applied bias, we observe a sharp peak in the spectral response in the red region near 700 nm. Simulation results obtained with the program ASCA are in agreement with the measurement and permit the explanation of the experimental data. In thick samples holes recombine or are trapped before reaching the contacts, and the conduction mechanism is fully electron dominated. As a consequence, the peak position in the spectral response is located near the optical band gap of the a-Si:H i-layer. (C) 2009 Elsevier B.V. All rights reserved.

The use of non-standard CT conversion ramps for Monte Carlo verification of 6 MV prostate IMRT plans

Monte Carlo (MC) dose calculation algorithms have been widely used to verify the accuracy of intensity-modulated radiotherapy (IMRT) dose distributions computed by conventional algorithms due to the ability to precisely account for the effects of tissue inhomogeneities and multileaf collimator characteristics. Both algorithms present, however, a particular difference in terms of dose calculation and report. Whereas dose from conventional methods is traditionally computed and reported as the water-equivalent dose (Dw), MC dose algorithms calculate and report dose to medium (Dm). In order to compare consistently both methods, the conversion of MC Dm into Dw is therefore necessary. This study aims to assess the effect of applying the conversion of MC-based Dm distributions to Dw for prostate IMRT plans generated for 6 MV photon beams. MC phantoms were created from the patient CT images using three different ramps to convert CT numbers into material and mass density: a conventional four material ramp (CTCREATE) and two simplified CT conversion ramps: (1) air and water with variable densities and (2) air and water with unit density. MC simulations were performed using the BEAMnrc code for the treatment head simulation and the DOSXYZnrc code for the patient dose calculation. The conversion of Dm to Dw by scaling with the stopping power ratios of water to medium was also performed in a post-MC calculation process. The comparison of MC dose distributions calculated in conventional and simplified (water with variable densities) phantoms showed that the effect of material composition on dose-volume histograms (DVH) was less than 1% for soft tissue and about 2.5% near and inside bone structures. The effect of material density on DVH was less than 1% for all tissues through the comparison of MC distributions performed in the two simplified phantoms considering water. Additionally, MC dose distributions were compared with the predictions from an Eclipse treatment planning system (TPS), which employed a pencil beam convolution (PBC) algorithm with Modified Batho Power Law heterogeneity correction. Eclipse PBC and MC calculations (conventional and simplified phantoms) agreed well (<1%) for soft tissues. For femoral heads, differences up to 3% were observed between the DVH for Eclipse PBC and MC calculated in conventional phantoms. The use of the CT conversion ramp of water with variable densities for MC simulations showed no dose discrepancies (0.5%) with the PBC algorithm. Moreover, converting Dm to Dw using mass stopping power ratios resulted in a significant shift (up to 6%) in the DVH for the femoral heads compared to the Eclipse PBC one. Our results show that, for prostate IMRT plans delivered with 6 MV photon beams, no conversion of MC dose from medium to water using stopping power ratio is needed. In contrast, MC dose calculations using water with variable density may be a simple way to solve the problem found using the dose conversion method based on the stopping power ratio.