Growth responses of Macrocystis pyrifera (Laminariales), Southern Chile, juvenile sporophytes to nutrient limitation

1st Mares Conference on Marine Ecosystems Health and Conservation. Olhão, Portugal 17-21 November 2014.

Estudo de tecnologias domóticas e a sua aplicação em projectos

Actualmente a área da domótica (automação de casas e edifícios) encontra-se em franca expansão, com principal relevância nos países mais desenvolvidos, com um crescimento de mercado de mais de 10% ao ano. Existem inúmeras razoes para a crescente implantação da domótica em edifícios, entre as quais a maior eficiência energética, o aumento da segurança e a redução do custo de aquisição das tecnologias. No que diz respeito as habitações particulares, acrescenta-se essencialmente o aumento do conforto devido ao grau de automação trazido pela domótica. Apesar da domótica não ser uma área cientifico-tecnológica recente, a rápida evolução das tecnologias associadas, nomeadamente a nível das redes de comunicação com e sem fios, foi uma das razoes fundamentais para a elaboração desta Tese. Acresce o facto de o candidato estar actualmente envolvido profissionalmente na área, pelo qual esta Tese assume uma particular importância. Realizou-se um estudo comparativo das tecnologias de domótica mais relevantes, escolhidas quer pelas suas características técnicas quer pela sua implantação de mercado e potencial futuro - KNX/EIB, LonWorks, HomePlug, ZigBee e Z-Wave. Destas, comprovou-se que as duas primeiras são aquelas que, actualmente, tem maior adequabilidade para serem aplicadas em projectos de domótica. Foi por isso efectuado um estudo mais elaborado das tecnologias LonWorks e KNX/EIB, incluindo a forma pratica de instalação/programação, a elaboração de dois demonstradores e de dois projectos (de acordo com um caderno de encargos real), usando as duas tecnologias. Concluiu-se que a tecnologia LonWorks apresenta vantagens no que respeita a escalabilidade (dimensão) dos sistemas. Em termos futuros, prevê-se a necessidade da interoperabilidade entre os nos/redes cablados (tradicionais) com nos/redes sem fio, seguindo a tendência para os ambientes inteligentes (“ambient intelligence/assisted living”, “smart spaces”, “ubiquitous computing).

Code offloading on real-time multimedia systems: a framework for handling code mobility and code offloading in a QoS aware environment

Actualmente, os smartphones e outros dispositivos móveis têm vindo a ser dotados com cada vez maior poder computacional, sendo capazes de executar um vasto conjunto de aplicações desde simples programas de para tirar notas até sofisticados programas de navegação. Porém, mesmo com a evolução do seu hardware, os actuais dispositivos móveis ainda não possuem as mesmas capacidades que os computadores de mesa ou portáteis. Uma possível solução para este problema é distribuir a aplicação, executando partes dela no dispositivo local e o resto em outros dispositivos ligados à rede. Adicionalmente, alguns tipos de aplicações como aplicações multimédia, jogos electrónicos ou aplicações de ambiente imersivos possuem requisitos em termos de Qualidade de Serviço, particularmente de tempo real. Ao longo desta tese é proposto um sistema de execução de código remota para sistemas distribuídos com restrições de tempo-real. A arquitectura proposta adapta-se a sistemas que necessitem de executar periodicamente e em paralelo mesmo conjunto de funções com garantias de tempo real, mesmo desconhecendo os tempos de execução das referidas funções. A plataforma proposta foi desenvolvida para sistemas móveis capazes de executar o Sistema Operativo Android.

Can ERASMUS mobility really help crossing borders? the in and out of a case-study

As lectures, but above all, as Erasmus....

Desesenvolvimento de recursos educativos para a área de matemática em dispositivos móveis

A combinação do avanço tecnológico com o crescimento da aquisição de dispositivos móveis refletiu-­‐se na vida diária das pessoas, sendo usado nas atividades de trabalho e lazer. A transposição dessa realidade para a sala de aula, não se fez esperar, inicialmente até de uma forma marginal mas acabando por ser aceite. Confrontada com esta nova realidade as autoridades educativas começaram a apoiar e a incentivar as instituições. O desenvolvimento de tecnologias como b-­‐learning, m-­‐learning e dos sistemas de aprendizagem (Learning Management System) deram uma grande contribuição para o desenvolvimento das tecnologias móveis no ensino, no entanto ainda hoje os intervenientes da educação, especialmente professores e alunos, sentem diversas necessidades. Neste contexto procedeu-­‐se ao desenvolvimento de um recurso educativo para a disciplina de matemática. Este recurso educativo está suportado numa plataforma que permite colocar conteúdos, visualiza-­‐los, alterá-­‐los e elimina-­‐los. Numa vertente mais lúdica, foi desenvolvido um jogo didático para um dispositivo móvel, neste caso o iPhone. Desta forma o aluno aprende sem se aperceber que está a aprender e pode faze-­‐lo em qualquer lugar e em qualquer período de tempo. Explorando, assim, a interatividade e a mobilidade.

Growth patterns in early childhood and the onset of menarche before age twelve

OBJECTIVE: To examine the relationship between growth patterns in early childhood and the onset of menarche before age 12. METHODS: The study included 2,083 women from a birth cohort study conducted in the city of Pelotas, Southern Brazil, starting in 1982. Anthropometric, behavioral, and pregnancy-related variables were collected through home interviews. Statistical analyses were performed using Pearson's chi-square and chi-square test for linear trends. A multivariable analysis was carried out using Poisson regression based on a hierarchical model. RESULTS: Mean age of menarche was 12.4 years old and the prevalence of menarche before age 12 was 24.3%. Higher weight-for-age, height-for-age, and weight-for-height z-scores at 19.4 and 43.1 months of age were associated with linear tendencies of increased prevalence and relative risks of the onset of menarche before age 12. Girls who experienced rapid growth in weight-for-age z-score from birth to 19.4 months of age and in weight-for-age or height-for-age z-scores from 19.4 to 43.1 months of age also showed higher risk of menarche before age 12. Higher risk was seen when rapid growth in weight-for-age z-score was seen during these age intervals and the highest risk was found among those in the first tertile of Williams' curve at birth. Rapid growth in weight-for-height z-score was not associated with menarche before age 12. CONCLUSIONS: Menarche is affected by nutritional status and growth patterns during early childhood. Preventing overweight and obesity during early childhood and keeping a "normal" growth pattern seem crucial for the prevention of health conditions during adulthood.

A multiresidue method for the analysis of carbamate and urea pesticides from soils by microwave-assisted extraction and liquid chromatography with photodiode array detection

A multiresidue approach using microwave-assisted extraction and liquid chromatography with photodiode array detection was investigated for the determination of butylate, carbaryl, carbofuran, chlorpropham, ethiofencarb, linuron,metobromuron, and monolinuron in soils. The critical parameters of the developed methodology were studied. Method validation was performed by analyzing freshly and aged spiked soil samples. The recoveries and relative standard deviations reached using the optimized conditions were between 77.0 ± 0.46% and 120 ± 2.9% except for ethiofencarb (46.4 ± 4.4% to 105 ± 1.6%) and butylate (22.1 ± 7.6% to 49.2 ± 11%). Soil samples from five locations of Portugal were analysed.

Determination of chlorfenvinphos in soils by microwave-assisted extraction and stripping voltammetry with an ultramicroelectrode

A methodology for the determination of the pesticide chlorfenvinphos by microwave-assisted solvent extraction and square-wave cathodic stripping voltammetry at a mercury film ultramicroelectrode in soil samples is proposed. Optimization of microwave solvent extraction performed with two soils, selected for having significantly different properties, indicated that the optimum solvent for extracting chlorfenvinphos is hexane-acetone (1:1, v/v). The voltammetric procedure is based on controlled adsorptive accumulation of the insecticide at the potential of -0.60 V (vs. Ag/AgCl) in the presence of Britton-Robinson buffer (pH 6.2). The detection limit obtained for a 10 s collection time was 3.0 x 10-8 mol l-1. The validity of the developed methodology was assessed by recovery experiments at the 0.100 µg g-1 level. The average recoveries and standard deviations for the global procedure reached byMASE-square-wave voltammetry were 90.2±2.8% and 92.1±3.4% for type I (soil rich in organic matter) and type II (sandy soil) samples, respectively. These results are in accordance to the expected values which show that the method has a good accuracy.

Determination of carbamate and urea pesticide residues in fresh vegetables using microwave-assisted extraction and liquid chromatography

An analytical multiresidue method for the simultaneous determination of seven pesticides in fresh vegetable samples, namely, courgette (Cucurbita pepo), cucumber (Cucumis sativus), lettuce (Lactuca sativa, Romaine and Iceberg varieties) and peppers (Capsicum sp.) is described. The procedure, based on microwave-assisted extraction (MAE) and analysis by liquid chromatography– photodiode array (LC–PDA) detection was applied to four carbamates (carbofuran, carbaryl, chlorpropham and EPTC) and three urea pesticides (monolinuron, metobromuron and linuron). Extraction solvent and the addition of anhydrous sodium sulphate to fresh vegetable homogenate before MAE were the parameters optimised for each commodity. Recovery studies were performed using spiked samples in the range 250–403 µgkg- 1 in each pesticide. The pesticide residues were extracted using 20mL acetonitrile at 60 ºC, for 10 min. Acceptable recoveries and RSDs were attained (overall average recovery of 77.2% and RSDs are lower than 11%). Detection limits ranged between 5.8 µgkg- 1 for carbaryl to 12.3 µgkg- 1 for carbofuran. The analytical protocol was applied for quality control of 41 fresh vegetable samples bought in Oporto Metropolitan Area (North Portugal). None of the samples contained any detectable amounts of the studied compounds.

Screening of carbamates and ureas in fresh and processed tomato samples using micowave-assisted extraction and liquid chromatography

An analytical method, based on microwave-assisted extraction and liquid chromatography with diode array detection, for the determination of six carbamate and three urea pesticides in fresh and processed tomato samples is described. Significant parameters affecting extraction efficiency were optimized. Under optimum microwave-assisted extraction conditions (20mL acetonitrile, for 10 minutes, at 60º C), pesticides were extracted with recoveries ranging from 57.6 to 102% (RSDs<7%). Quantification limits between 6.5 and 39.6 µg=kg were obtained. A total number of 28 different fresh tomato samples and 6 processed tomato products were analysed. Confirmation of suspicious samples was performed by LC-MS.

Academic mobility: a non-Machiavellian means to global citizenship

Although Mobility is a trendy and an important keyword in education matters, it has been a knowledge tool since the beginning of times, namely the Classical Antiquity, when students were moving from place to place following the masters. Over the time, different types of academic mobility can be found and this tool has been taken both by the education and business sector as almost a compulsory process since the world has gone global. Mobility is, of course, not an end but a means. And as far as academic mobility is concerned it is above all a means to get knowledge, being it theoretical or practical. But why does it still make sense to move from one place to another to get knowledge if never as before we have heaps of information and experiences available around us, either through personal contacts, in books, journals, newspapers or online? With this paper we intend to discuss the purpose of international mobility in the global world of the 21st century as a means to the development of world citizens able to live, work and learn in different and unfamiliar contexts. Based on our own experience as International Coordinator in a Higher Education Institution (HEI) over the last 8 years, on the latest research on academic mobility and still on studies on employability we will show how and why academic mobility can develop skills either in students or in other academic staff that are hardly possible to build in a classroom, or in a non-mobile academic or professional experience and that are highly valued by employers and society in general.

Development and validation of a novel method for the analysis of chlorinated pesticides in soils using microwave-assisted extraction–headspace solid phase microextraction and gas chromatography–tandem mass spectrometry

A new procedure for determining eleven organochlorine pesticides in soils using microwave-assisted extraction (MAE) and headspace solid phase microextraction (HS-SPME) is described. The studied pesticides consisted of mirex, α- and γ-chlordane, p,p’-DDT, heptachlor, heptachlor epoxide isomer A, γ-hexachlorocyclohexane, dieldrin, endrin, aldrine and hexachlorobenzene. The HS-SPME was optimized for the most important parameters such as extraction time, sample volume and temperature. The present analytical procedure requires a reduced volume of organic solvents and avoids the need for extract clean-up steps. For optimized conditions the limits of detection for the method ranged from 0.02 to 3.6 ng/g, intermediate precision ranged from 14 to 36% (as CV%), and the recovery from 8 up to 51%. The proposed methodology can be used in the rapid screening of soil for the presence of the selected pesticides, and was applied to landfill soil samples.

Symphysis-fundal height curve in the diagnosis of fetal growth deviations

OBJECTIVE: To validate a new symphysis-fundal curve for screening fetal growth deviations and to compare its performance with the standard curve adopted by the Brazilian Ministry of Health. METHODS: Observational study including a total of 753 low-risk pregnant women with gestational age above 27 weeks between March to October 2006 in the city of João Pessoa, Northeastern Brazil. Symphisys-fundal was measured using a standard technique recommended by the Brazilian Ministry of Health. Estimated fetal weight assessed through ultrasound using the Brazilian fetal weight chart for gestational age was the gold standard. A subsample of 122 women with neonatal weight measurements was taken up to seven days after estimated fetal weight measurements and symphisys-fundal classification was compared with Lubchenco growth reference curve as gold standard. Sensitivity, specificity, positive and negative predictive values were calculated. The McNemar χ2 test was used for comparing sensitivity of both symphisys-fundal curves studied. RESULTS: The sensitivity of the new curve for detecting small for gestational age fetuses was 51.6% while that of the Brazilian Ministry of Health reference curve was significantly lower (12.5%). In the subsample using neonatal weight as gold standard, the sensitivity of the new reference curve was 85.7% while that of the Brazilian Ministry of Health was 42.9% for detecting small for gestational age. CONCLUSIONS: The diagnostic performance of the new curve for detecting small for gestational age fetuses was significantly higher than that of the Brazilian Ministry of Health reference curve.

Determination of ametryn in soils via microwave-assisted solvent extraction coupled to anodic stripping voltammetry with a gold ultramicroelectrode

An extraction-anodic adsorptive stripping voltammetric procedure using microwave-assisted solvent extraction and a gold ultramicroelectrode was developed for determining the pesticide ametryn in soil samples. The method is based on the use of acetonitrile as extraction solvent and on controlled adsorptive accumulation of the herbicide at the potential of 0.50 V (vs. Ag/AgCl) in the presence of Britton-Robinson buffer (pH 3.3). Soil sample extracts were analysed directly after drying and redissolution with the supporting electrolyte but without other pre-treatment. The limit of detection obtained for a 10 s collection time was 0.021 µg g-1. Recovery experiments for the global procedure, at the 0.500 µg g-1 level, gave satisfactory mean and standard deviation results which were comparable to those obtained by HPLC with UV detection.

Analysis of PCBs in soils and sediments by microwave-assisted extraction, headspace-SPME and high resolution gas chromatography with ion-trap tandem mass spectrometry

A procedure for the determination of seven indicator PCBs in soils and sediments using microwave-assisted extraction (MAE) and headspace solid-phase microextraction (HS-SPME) prior to GC-MS/MS is described. Optimization of the HS-SPME was carried out for the most important parameters such as extraction time, sample volume and temperature. The adopted methodology has reduced consumption of organic solvents and analysis runtime. Under the optimized conditions, the method detection limit ranged from 0.6 to 1 ng/g when 5 g of sample was extracted, the precision on real samples ranged from 4 to 21% and the recovery from 69 to 104%. The proposed method, which included the analysis of a certified reference material in its validation procedure, can be extended to several other PCBs and used in the monitoring of soil or sediments for the presence of PCBs.