Soleus activity in post-stroke subjects: movement sequence from standing to sitting

O documento em anexo encontra-se na versão post-print (versão corrigida pelo editor).

Natural organic matter fractionation along the treatment of water for human consumption

The main objective of this study was to characterize the organic matter present in raw water and along the treatment process, as well as its seasonal variation. A natural organic matter fractionation approach has been applied to Lever water treatment plant located in Douro River, in Oporto (Portugal). The process used was based on the sorption of dissolved organic matter in different types of ion exchange resins, DAX-8, DAX-4 and IRA-958, allowing its separation into four fractions: very hydrophobic acids (VHA), slightly hydrophobic acids (SHA), charged hydrophilic (CHA) and hydrophilic neutral (NEU). The dissolved organic carbon (DOC) determination was used to quantify dissolved organic matter. Samples were collected monthly, during approximately one year, from raw water captured at the surface and under the bed of the river, and after each step of the treatment: pre-filtration in sand/anthracite filters, ozonation, coagulation/flocculation, counter current dissolved air flotation and filtration (CoCoDAFF) and chlorination. The NEU fraction showed a seasonal variation, with maximum values in autumn for the sampling points corresponding to raw water captured at the surface and under the bed of the river. It was usually the predominating fraction and did not show a significant decrease throughout the treatment. Nevertheless their low concentration, the same occurred for the CHA and VHA fractions. There was an overall decrease in the SHA fraction throughout the water treatment (especially after CoCoDAFF and ozonation) as well as in the DOC. The TSUVA254 values obtained for raw water generally varied between 2.0 and 4.0 L mgC-1 m-1 and between 0.75 and 1.78 L mgC-1 m-1 for treated water. It was observed a decrease of TSUVA values along the treatment, especially after ozonation. These results may contribute to a further optimization in the process of treating water for human consumption.

Eficácia do Constraint-Induced Movement Therapy, em utentes com sequelas de Acidente Vascular Encefálico, até 9 meses

O Acidente Vascular Encefálico é uma das principais causas de morte, tornando-se cada vez mais iminente processos de reabilitação que minimizem as sequelas, nomeadamente as limitações do membro superior que dificultam o envolvimento em atividades da vida diária. O Constraint-Induced Movement Therapy, surge como uma abordagem que incrementa o uso do membro superior mais afetado. A presente investigação trata-se de um estudo de casos múltiplos. Pretende-se verificar se existem melhorias na funcionalidade do membro superior mais afetado, analisar em que atividades da vida diária são visíveis melhorias funcionais e compreender se o maior envolvimento nas atividades diárias está diretamente relacionado com a melhoria na capacidade funcional. Pretende-se ainda que os valores obtidos no Wolf Motor Function Test sejam um contributo para a sua validação para a população portuguesa. Utilizou-se um questionário para recolha de dados pessoais e clínicos (amplitudes de movimento, dor e espasticidade); o Wolf Motor Function Test e o Action Research Arm Test para verificar a funcionalidade do membro superior mais afetado; e a Motor Activity Log que avalia o envolvimento em atividades da vida diária. O grupo é constituído por 3 utentes que sofreram um primeiro Acidente Vascular Encefálico até 9 meses de evolução, internados na Santa Casa da Misericórdia de Monção e que cumpriam os critérios de inclusão. O programa foi implementado três horas/dia, durante 10 dias, mantendo a restrição no membro superior menos afetado durante 90% do dia acordado. Como se trata de um estudo de casos múltiplos, analisou-se cada participante individualmente e verificou-se a diferença entre os resultados finais e iniciais para cada uma das variáveis. Os resultados obtidos revelam ganhos na amplitude de movimento, velocidade de execução e capacidade funcional do membro superior mais afetado, nomeadamente nas funções de preensão e pinça da mão, bem como se testemunhou minimização do fenómeno learned nonuse. Verificaram-se ganhos funcionais em todos os participantes nas atividades da vida diária apesar de serem diferentes de participante para participante. Dois participantes afirmaram que voltariam a participar no programa.Conclui-se, assim que a técnica resulta em ganhos funcionais nestes utentes, indicando um caminho alternativo a outras abordagens de reabilitação.

Efetividade do conceito de Mulligan comparativamente ao exercício terapêutico supervisionado na diminuição da dor no ombro em atletas de Polo Aquático

Introdução: A aplicação das técnicas de Mulligan têm como objetivo reduzir a dor, aumentar as amplitudes articulares e melhorar a funcionalidade, assim como sobre a aplicação de um programa exercícios supervisionados ao complexo articular do ombro. O propósito de um programa de exercícios do ombro pode ser dirigido para o alívio da dor, para o equilíbrio e aumento da força muscular, assim como para restabelecer sem dor as amplitudes articulares de movimento. Objetivos: Este estudo teve como objectivo comparar a eficácia do conceito de Mulligan com um programa de exercícios terapêuticos na diminuição da dor no ombro em atletas de Polo Aquático. Métodos: Realizou-se um estudo quase-experimental, sendo a amostra composta por 13 atletas do sexo masculino e 11 atletas do sexo feminino, que apresentavam dor na região do ombro, com idades compreendidas entres os 19 e os 32 anos de idade (n=24). Foi aplicado um questionário para a recolha da informação relativa à caracterização do atleta e á presença de dor. A avaliação foi realizada em diversos momentos, nomeadamente avaliação pré tratamento, avaliação pós primeira, segunda e terceira semana de tratamento, utilizando o instrumento EVA. Estatística: Procedeu-se à análise estatística descritiva e recorreu-se ao teste de Willcoxon, Teste T para testar associação entre a intensidade da dor e os diferentes momentos da avaliação da dor, a Teste de Willcoxon para testar associação entre a intensidade da dor entre os diferentes momentos de avaliação. Foi usado um nível de significância de 0,05. Resultados: Os resultados demonstram que nos dois grupos os atletas tiveram diminuição da intensidade da dor no ombro, embora se tenha verificado que a intervenção com MVM produz resultados mais rápidos e eficazes na diminuição da intensidade da dor, comparativamente á intervenção com exercícios terapêuticos supervisionados em atletas de Polo Aquático com dor no ombro. Conclusão: A intervenção com mobilização com movimento teve maior eficácia na diminuição intensidade da dor comparativamente á intervenção com exercícios terapêuticos supervisionados em atletas com dor no ombro.

Modelação do transporte e dispersão de um marcador corado no Rio Febros

O rio Febros é um pequeno curso de água, situado no concelho de Vila Nova de Gaia, com cerca de 15 km de extensão, cuja bacia hidrográfica ocupa uma área de aproximadamente 35,4 km2. Nasce em Seixezelo e desagua na margem esquerda do Rio Douro no Cais do Esteiro, em Avintes. Em Maio de 2008, um acidente de viação teve como consequência o derrame de cerca de quatro toneladas de ácido clorídrico que rapidamente convergiu às águas do rio. Apenas um dia depois, o pH desceu para três e muitos foram os peixes que morreram. A solução adoptada para evitar o desaire foi introduzir milhares de litros de água de modo a diluir o ácido presente, ao longo de todo o curso de água. Tal facto não evitou a destruição de parte de um ecossistema, que ainda nos dias de hoje se encontra em recuperação. De forma a avaliar-se o impacto destas possíveis perturbações sejam estas de origem antropogénica ou natural é necessário possuir conhecimentos dos processos químicos tais como a advecção, a mistura devida à dispersão e a transferência de massa ar/água. Estes processos irão determinar o movimento e destino das substâncias que poderão ser descarregadas no rio. Para tal, recorrer-se-á ao estudo hidrogeométrico do curso de água assim como ao estudo do comportamento de um marcador, simulando uma possível descarga. A rodamina WT será o marcador a ser utilizado devido à panóplia de características ambientalmente favoráveis. Os estudos de campo com este corante, realizados em sequência de descarga previamente estudada, fornecem uma das melhores fontes de informação para verificação e validação de modelos hidráulicos utilizados em estudos de qualidade de águas e protecção ambiental. Escolheram-se dois pontos de descarga no Febros, um em Casal Drijo e outro no Parque Biológico de Gaia, possuindo cada um deles, a jusante, duas estações de monitorização. Pelo modelo ADE os valores obtidos para o coeficiente de dispersão longitudinal para as estações Pontão d’ Alheira, Pinheiral, Menesas e Giestas foram, respectivamente, 0,3622; 0,5468; 1,6832 e 1,7504 m2/s. Para a mesma sequência de estações, os valores da velocidade de escoamento obtidos neste trabalho experimental foram de 0,0633; 0,0684; 0,1548 e 0,1645 m/s. Quanto ao modelo TS, os valores obtidos para o coeficiente de dispersão longitudinal para as estações Pontão d’ Alheira, Pinheiral, Menesas e Giestas foram, respectivamente, 0,2339; 0,1618; 0,5057e 1,1320 m2/s. Para a mesma sequência de estações, os valores da velocidade de escoamento obtidos neste trabalho experimental foram de 0,0652; 0,0775; 0,1891 e 0,1676 m/s. Os resultados foram ajustados por um método directo, o método dos momentos, e por dois métodos indirectos, os modelos ADE e TS. O melhor ajuste corresponde ao modelo TS onde os valores do coeficiente de dispersão longitudinal e da velocidade de escoamento são aqueles que melhor se aproximam da realidade. Quanto ao método dos momentos, o valor estimado para a velocidade é de 0,162 m/s e para o coeficiente de dispersão longitudinal de 9,769 m2/s. Não obstante, a compreensão da hidrodinâmica do rio e das suas características, bem como a adequação de modelos matemáticos no tratamento de resultados formam uma estratégia de protecção ambiental inerente a futuros impactos que possam suceder.

Sensors for the detection and quantification of bacterial contamination in water for human use

The deterioration of water quality by Cyanobacteria cause outbreaks and epidemics associated with harmful diseases in Humans and animals because of the toxins that they release. Microcystin-LR is one of the hepatotoxins most widely studied and the World Health Organization, recommend a maximum value of 1mgL 1 in drinking water. Highly specific recognition molecules, such as molecular imprinted polymers are developed to quantify microcystins in waters for human use and shown to be of great potential in the analysis of these kinds of samples. The obtained results were auspicious, the detection limit found, 1.5mgL 1, being of the same order of magnitude as the guideline limit recommended by the WHO. This technology is very promising because the sensors are stable and specific, and the technology is inexpensive and allows for rapid on-site monitoring.

Electrochemical study of butylate: application to the analysis of water

The electroactivity of butylate (BTL) is studied by cyclic voltammetry (CV) and square wave voltammetry (SWV) at a glassy carbon electrode (GCE) and a hanging mercury drop electrode (HMDE). Britton–Robinson buffer solutions of pH 1.9–11.5 are used as supporting electrolyte. CV voltammograms using GCE show a single anodic peak regarding the oxidation of BTL at +1.7V versus AgCl/ Ag, an irreversible process controlled by diffusion. Using a HMDE, a single cathodic peak is observed, at 1.0V versus AgCl/Ag. The reduction of BTL is irreversible and controlled by adsorption. Mechanism proposals are presented for these redox transformations. Optimisation is carried out univaryingly. Linearity ranges were 0.10–0.50 mmol L-1 and 2.0–9.0 µmolL-1 for anodic and cathodic peaks, respectively. The proposed method is applied to the determination of BTL in waters. Analytical results compare well with those obtained by an HPLC method.

Use and reuse of SPE disks for the determination of pyrethroids in water by GC-ECD

Seven pyrethroids (bifenthrin, fenpropathrin, k-cyhalothrin, permethrin, a-cypermethrin, fenvalerate, and deltamethrin) were extracted from water using C18 solid-phase extraction disks, followed by gas chromatography with an electron capture detector (GC-ECD) analysis. The limits of detection in water samples ranged from 0.5 ng L-1 (fenpropathrin) to 110 ng L- 1 (permethrin), applying the calibration graph. The effects of different numbers of (re)utilizations of the same disks (up to four times with several concentrations) on the recoveries of the pyrethroids were considered. The recoveries were all between 70 and 120% after four utilizations of the same disk. There was no difference between these recoveries at a confidence level of 95%.

Soil remediation time to achieve clean-up goals I: influence of soil water content

The current models are not simple enough to allow a quick estimation of the remediation time. This work reports the development of an easy and relatively rapid procedure for the forecasting of the remediation time using vapour extraction. Sandy soils contaminated with cyclohexane and prepared with different water contents were studied. The remediation times estimated through the mathematical fitting of experimental results were compared with those of real soils. The main objectives were: (i) to predict, through a simple mathematical fitting, the remediation time of soils with water contents different from those used in the experiments; (ii) to analyse the influence of soil water content on the: (ii1) remediation time; (ii2) remediation efficiency; and (ii3) distribution of contaminants in the different phases present into the soil matrix after the remediation process. For sandy soils with negligible contents of clay and natural organic matter, artificially contaminated with cyclohexane before vapour extraction, it was concluded that (i) if the soil water content belonged to the range considered in the experiments with the prepared soils, then the remediation time of real soils of similar characteristics could be successfully predicted, with relative differences not higher than 10%, through a simple mathematical fitting of experimental results; (ii) increasing soil water content from 0% to 6% had the following consequences: (ii1) increased remediation time (1.8–4.9 h, respectively); (ii2) decreased remediation efficiency (99–97%, respectively); and (ii3) decreased the amount of contaminant adsorbed onto the soil and in the non-aqueous liquid phase, thus increasing the amount of contaminant in the aqueous and gaseous phases.

Soil remediation time to achieve clean-up goals II: influence of natural organic matter and water contents

This work reports a relatively rapid procedure for the forecasting of the remediation time (RT) of sandy soils contaminated with cyclohexane using vapour extraction. The RT estimated through the mathematical fitting of experimental results was compared with that of real soils. The main objectives were: (i) to predict the RT of soils with natural organic matter (NOM) and water contents different from those used in experiments; and (ii) to analyse the time and efficiency of remediation, and the distribution of contaminants into the soil matrix after the remediation process, according to the soil contents of: (ii1) NOM; and (ii2) water. For sandy soils with negligible clay contents, artificially contaminated with cyclohexane before vapour extraction, it was concluded that: (i) if the NOM and water contents belonged to the range of the prepared soils, the RT of real soils could be predicted with relative differences not higher than 12%; (ii1) the increase of NOM content from 0% to 7.5% increased the RT (1.8–13 h) and decreased the remediation efficiency (RE) (99–90%) and (ii2) the increase of soil water content from 0% to 6% increased the RT (1.8–4.9 h) and decreased the RE (99–97%). NOM increases the monolayer capacity leading to a higher sorption into the solid phase. Increasing of soil water content reduces the mass transfer coefficient between phases. Concluding, NOM and water contents influence negatively the remediation process, turning it less efficient and more time consuming, and consequently more expensive.

Remediation efficiency of vapour extraction of sandy soils contaminated with cyclohexane: influence of air flow rate, water and natural organic matter content

Abstract This work reports the analysis of the efficiency and time of soil remediation using vapour extraction as well as provides comparison of results using both, prepared and real soils. The main objectives were: (i) to analyse the efficiency and time of remediation according to the water and natural organic matter content of the soil; and (ii) to assess if a previous study, performed using prepared soils, could help to preview the process viability in real conditions. For sandy soils with negligible clay content, artificially contaminated with cyclohexane before vapour extraction, it was concluded that (i) the increase of soil water content and mainly of natural organic matter content influenced negatively the remediation process, making it less efficient, more time consuming, and consequently more expensive; and (ii) a previous study using prepared soils of similar characteristics has proven helpful for previewing the process viability in real conditions.

Groundwater from infiltration galleries used for small public water supply systems: contamination with pesticides and endocrine disruptors

Infiltration galleries are among the oldest known means used for small public water fountains. Owing to its ancestral origin they are usually associated with high quality water. Thirty-one compounds, including pesticides and estrogens from different chemical families, were analysed in waters from infiltration galleries collected in Alto Douro Demarcated Wine region (North of Portugal). A total of twelve compounds were detected in the water samples. Nine of these compounds are described as presenting evidence or potential evidence of interfering with the hormone system of humans and wildlife. Although concentrations of the target analytes were relatively low, many of them below their limit of quantification, four compounds were above quantification limit and two of them even above the legal limit of 0.1 lg/L: dimethoate (30.38 ng/L), folpet (64.35 ng/L), terbuthylazine-desethyl (22.28 to 292.36 ng/L) and terbuthylazine (22.49 to 369.33 ng/L).

Evaluation of the total antioxidant capacity of flavored water and electrochemical purine damage by sulfate radicals using a purine-based sensor

In this study, a method for the electrochemical quantification of the total antioxidant capacity (TAC) in beverages was developed. The method is based on the oxidative damage to the purine bases, adenine or guanine, that are immobilized on a glassy carbon electrode (GCE) surface. The oxidative lesions on the DNA bases were promoted by the sulfate radical generated by the persulfate/iron(II) system. The presence of antioxidants on the reactive system promoted the protection of the DNA bases immobilized on the GCE by scavenging the sulfate radical. Square-wave voltammetry (SWV) was the electrochemical technique used to perform this study. The efficiencies of five antioxidants (ascorbic acid, gallic acid, caffeic acid, coumaric acid and resveratrol) in scavenging the sulfate radical and, therefore, their ability to protect the purine bases immobilized on the GCE were investigated. These results demonstrated that the purine-based biosensor is suitable for the rapid assessment of the TAC in flavors and flavored water.

Quantification of endocrine disruptors and pesticides in water by gas chromatography–tandem mass spectrometry. Method validation using weighted linear regression schemes

Amulti-residue methodology based on a solid phase extraction followed by gas chromatography–tandem mass spectrometry was developed for trace analysis of 32 compounds in water matrices, including estrogens and several pesticides from different chemical families, some of them with endocrine disrupting properties. Matrix standard calibration solutions were prepared by adding known amounts of the analytes to a residue-free sample to compensate matrix-induced chromatographic response enhancement observed for certain pesticides. Validation was done mainly according to the International Conference on Harmonisation recommendations, as well as some European and American validation guidelines with specifications for pesticides analysis and/or GC–MS methodology. As the assumption of homoscedasticity was not met for analytical data, weighted least squares linear regression procedure was applied as a simple and effective way to counteract the greater influence of the greater concentrations on the fitted regression line, improving accuracy at the lower end of the calibration curve. The method was considered validated for 31 compounds after consistent evaluation of the key analytical parameters: specificity, linearity, limit of detection and quantification, range, precision, accuracy, extraction efficiency, stability and robustness.

Estimation of pollutant partition in sandy soils with different water contents

The objectives of this work were: (1) to identify an isotherm model to relate the contaminant contents in the gas phase with those in the solid and non-aqueous liquid phases; (2) to develop a methodology for the estimation of the contaminant distribution in the different phases of the soil; and (3) to evaluate the influence of soil water content on the contaminant distribution in soil. For sandy soils with negligible contents of clay and natural organic matter, contaminated with benzene, toluene, ethylbenzene, xylene, trichloroethylene (TCE), and perchloroethylene (PCE), it was concluded that: (1) Freundlich’s model showed to be adequate to relate the contaminant contents in the gas phase with those in the solid and non-aqueous liquid phases; (2) the distribution of the contaminants in the different phases present in the soil could be estimated with differences lower than 10% for 83% of the cases; and (3) an increase of the soil water content led to a decrease of the amount of contaminant in the solid and non-aqueous liquid phases, increasing the amount in the other phases.