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.

Common genetic polymorphisms in the ABCB1 gene are associated with risk of major depressive disorder in male Portuguese individuals

Major depressive disorder (MDD) is a highly prevalent disorder, which has been associated with an abnormal response of the hypothalamus–pituitary–adrenal (HPA) axis. Reports have argued that an abnormal HPA axis response can be due to an altered P-Glycoprotein (P-GP) function. This argument suggests that genetic polymorphisms in ABCB1 may have an effect on the HPA axis activity; however, it is still not clear if this influences the risk of MDD. Our study aims to evaluate the effect of ABCB1 C1236T, G2677TA and C3435T genetic polymorphisms on MDD risk in a subset of Portuguese patients. DNA samples from 80 MDD patients and 160 control subjects were genotyped using TaqMan SNP Genotyping assays. A significant protection for MDD males carrying the T allele was observed (C1236T: odds ratio (OR) = 0.360, 95% confidence interval [CI]: [0.140– 0.950], p = 0.022; C3435T: OR= 0.306, 95% CI: [0.096–0.980], p = 0.042; and G2677TA: OR= 0.300, 95% CI: [0.100– 0.870], p = 0.013). Male Portuguese individuals carrying the 1236T/2677T/3435T haplotype had nearly 70% less risk of developing MDD (OR = 0.313, 95% CI: [0.118–0.832], p = 0.016, FDR p = 0.032). No significant differences were observed regarding the overall subjects. Our results suggest that genetic variability of the ABCB1 is associated with MDD development in male Portuguese patients. To the best of our knowledge, this is the first report in Caucasian samples to analyze the effect of these ABCB1 genetic polymorphisms on MDD risk.

Sorption of phenanthrene on agricultural soils

Polyaromatic hydrocarbon (PAH) sorption to soil is a key process deciding the transport and fate of PAH, and potential toxic impacts in the soil and groundwater ecosystems, for example in connection with atmospheric PAH deposition on soils. There are numerous studies on PAH sorption in relatively low organic porous media such as urban soils and groundwater sediments, but less attention has been given to cultivated soils. In this study, the phenanthrene partition coefficient, KD (liter per kilogram), was measured on 143 cultivated Danish soils (115 topsoils, 0–0.25-m soil depth and 28 subsoils, 0.25–1-m depth) by the single-point adsorption method. The organic carbon partition coefficient, KOC (liter per kilogram) for topsoils was found generally to fall between the KOC values estimated by the two most frequently used models for PAH partitioning, the Abdul et al. (Hazardous Waste & Hazardous Materials 4(3):211– 222, 1987) model and Karickhoff et al. (Water Research 13:241–248, 1979) model. A less-recognized model by Karickhoff (Chemosphere 10:833–846, 1981), yielding a KOC of 14,918 Lkg−1, closely corresponded to the average measured KOC value for the topsoils, and this model is therefore recommended for prediction of phenanthrene mobility in cultivated topsoils. For lower subsoils (0.25–1-m depth), the KOC values were closer to and mostly below the estimate by the Abdul et al. (Hazardous Waste & Hazardous Materials 4(3):211–222, 1987) model. This implies a different organic matter composition and higher PAH sorption strength in cultivated topsoils, likely due to management effects including more rapid carbon turnover. Finally, we applied the recent Dexter et al. (Geoderma 144:620–627, 2008) theorem, and calculated the complexed organic carbon and non-complexed organic carbon fractions (COC and NCOC, grams per gram). Multiple regression analyses showed that the NCOC-based phenanthrene partition coefficient (KNCOC) could be markedly higher than the COCbased partition coefficient (KCOC) for soils with a clay/OC ratio <10. This possibly higher PAH sorption affinity to the NCOC fraction needs further investigations to develop more realistic and accurate models for PAH mobility and effects in the environment, also with regard to colloid-facilitated PAH transport.

O conhecimento matemático dos estudantes no início da licenciatura em educação básica: um projeto envolvendo três escolas superiores de educação

O novo modelo de formação inicial (Decreto-Lei 43/2007) exige que os futuros professores do 1.º e 2.º ciclos do ensino básico e os futuros educadores de infância façam pelo menos 30 ECTS de formação em Matemática na Licenciatura em Educação Básica (LEB), mas a forma e o conteúdo desta formação é da responsabilidade de cada instituição, que define as unidades curriculares, o seu conteúdo e a forma como são lecionadas. Sabe-se que, para além do conteúdo, a forma como o professor aprende tem uma forte influência na forma como vai ensinar. Assim, todos estes aspetos precisam de ser discutidos, tendo por base a investigação já realizada em Portugal e noutros países. Partindo da assunção de que o conhecimento do professor constitui um fator decisivo na interpretação e implementação do currículo e da necessidade de uma discussão alargada de qual deverá ser o conteúdo da formação em Matemática na LEB, as Escolas Superiores de Educação de Lisboa, de Viana do Castelo e de Viseu iniciaram um projeto de investigação que tem como principal objetivo compreender de que modo a formação inicial contribui para o desenvolvimento do conhecimento do professor em Matemática e em Ensino da Matemática e como pode este ser promovido. Uma das questões que o projeto visa investigar é que conhecimento de conteúdo matemático têm os estudantes quando iniciam o curso da LEB.Para caracterizar o conhecimento matemático dos estudantes da LEB, à entrada no curso, foi elaborado um teste diagnóstico, que foi aplicado nas três Escolas Superiores de Educação, em outubro de 2011, a todos os alunos a iniciar o 1.º ano, num total de 268: 143 em Lisboa, 51 em Viseu e 74 em Viana do Castelo. Neste artigo é apresentada uma análise dos principais resultados deste teste bem como as questões e dilemas que aqueles resultados nos colocam.

Idosos com e sem plano de saúde e características socioepidemiológicas associadas

OBJETIVO: Analisar fatores epidemiológicos e sociodemográficos associados à saúde de idosos com ou sem plano de saúde. MÉTODOS: Foram realizadas entrevistas com 2.143 pessoas de 60 anos e mais, no município de São Paulo, em 2000 e 2006. A variável dependente, dicotômica, foi ter ou não plano de saúde. As variáveis independentes abrangeram características sociodemográficas e de condição de saúde. Foram descritas as proporções encontradas para as variáveis analisadas e desenvolvido modelo de regressão logística que considerou significantes as variáveis com p < 0,05. RESULTADOS: Houve diferenças, favoráveis aos titulares de planos, para renda e escolaridade. O grupo sem planos privados realizou menos prevenção contra neoplasias e mais contra doenças respiratórias; esperou mais para ter acesso a consultas de saúde; realizou menos exames pós-consulta; referiu menor número de doenças; teve maior proporção de avaliação negativa da própria saúde e relatou mais episódios de queda. Os titulares de planos relataram menor adesão à vacinação e, dentre os que foram internados, 11,1% em 2000 e 17,9% em 2006 tiveram esse procedimento custeado pelo Sistema Único de Saúde. A única doença associada à condição de titular de plano privado foi a osteoporose. CONCLUSÕES: Há diferenças representadas pela renda e pela escolaridade favoráveis aos titulares de planos e seguros privados, as quais estão relacionadas com o uso de serviços e com os determinantes sociais de saúde.

A survey in Portuguese X-ray fluoroscopy equipment: dose rates and image quality

X-ray fluoroscopy is essential in both diagnosis and medical intervention, although it may contribute to significant radiation doses to patients that have to be optimised and justified. Therefore, it is crucial to the patient to be exposed to the lowest achievable dose without compromising the image quality. The purpose of this study was to perform an analysis of the quality control measurements, particularly dose rates, contrast and spatial resolution of Portuguese fluoroscopy equipment and also to provide a contribution to the establishment of reference levels for the equipment performance parameters. Measurements carried out between 2007 and 2013 on 143 fluoroscopy equipment distributed by 34 nationwide health units were analysed. The measurements suggest that image quality and dose rates of Portuguese equipment are congruent with other studies, and in general, they are as per the Portuguese law. However, there is still a possibility of improvements intending optimisation at a national level.

Effects of irregular-shift work and physical activity on cardiovascular risk factors in truck drivers

OBJECTIVE: To analyze the putative effect of type of shift and its interaction with leisure-time physical activity on cardiovascular risk factors in truck drivers.METHODS: A cross-sectional study was undertaken on 57 male truck drivers working at a transportation company, of whom 31 worked irregular shifts and 26 worked on the day-shift. Participants recorded their physical activity using the International Physical Activity Questionnaire along with measurements of blood pressure, body mass index and waist-hip ratio. Participants also provided a fasting blood sample for analysis of lipid-related outcomes. Data were analyzed using a factorial model which was covariate-controlled for age, smoking, work demand, control at work and social support.RESULTS: Most of the irregular-shift and day-shift workers worked more than 8 hours per day (67.7% and 73.1%, respectively). The mean duration of experience working the irregular schedule was 15.7 years. Day-shift workers had never engaged in irregular-shift work and had been working as a truck driver for 10.8 years on average. The irregular-shift drivers had lower work demand but less control compared to day-shift drivers (p < 0.05). Moderately-active irregular-shift workers had higher systolic and diastolic arterial pressures (143.7 and 93.2 mmHg, respectively) than moderately-active day-shift workers (116 and 73.3 mmHg, respectively) (p < 0.05) as well as higher total cholesterol concentrations (232.1 and 145 mg/dl, respectively) (p = 0.01). Irrespective of their physical activity, irregular-shift drivers had higher total cholesterol and LDL-cholesterol concentrations (211.8 and 135.7 mg/dl, respectively) than day-shift workers (161.9 and 96.7 mg/dl, respectively (ANCOVA, p < 0.05).CONCLUSIONS: Truck drivers are exposed to cardiovascular risk factors due to the characteristics of the job, such as high work demand, long working hours and time in this profession, regardless of shift type or leisure-time physical activity.

Power Producers Trading Electricity in Both Pool and Forward Markets

The electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. This article addresses the challenge of maximizing the profit (or return) of power producers through the optimization of their share of customers. Power producers have fixed production marginal costs and decide the quantity of energy to sell in both day-ahead markets and a set of target clients, by negotiating bilateral contracts involving a three-rate tariff. Producers sell energy by considering the prices of a reference week and five different types of clients with specific load profiles. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.

Prevalência e fatores associados aos comportamentos sedentários em adolescentes

OBJETIVO Analisar a prevalência e fatores associados aos comportamentos sedentários em adolescentes. MÉTODOS Estudo transversal com adolescentes de 10 a 17 anos de idade, de ambos os sexos, pertencentes a uma coorte de nascimentos entre 1994-1999 na cidade de Cuiabá, Mato Grosso, Brasil. Para o levantamento dos dados, foi utilizado um questionário contendo informações sociodemográficas, econômicas e de estilo de vida e aferição de dados antropométricos. Determinou-se como comportamento sedentário o uso de televisão e/ou computador/vídeo games por um tempo igual ou superior a 4 horas/dia. Avaliou-se a associação de comportamentos sedentários com o índice de massa corporal, tanto na infância quanto na adolescência, e com variáveis sociodemográficas e comportamentais por meio de regressão logística hierarquizada. RESULTADOS A prevalência global de comportamentos sedentários foi de 58,1%. Dos 1.716 adolescentes estudados, 50,7% (n = 870) eram do sexo masculino. Na análise multivariada, após ajuste para fatores de confusão, as variáveis que permaneceram associadas com os comportamentos sedentários foram: idade (14 anos ou mais) (OR = 3,51; IC95% 2,19;5,60); classe econômica elevada (OR = 3,83; IC95% 2,10;7,01); maior nível de escolaridade da mãe (OR = 1,81; IC95% 1,09;3,01); residir no interior (OR = 0,49; IC95% 0,30;0,81); atividade física insuficiente (OR = 1,25; IC95% 1,02;1,53); experimentação de bebidas alcoólicas (OR = 1,34; IC95% 1,08;1,66) e excesso de peso na adolescência (OR = 1,33; IC95% 1,06;1,68). CONCLUSÕES A elevada proporção de adolescentes em atividades sedentárias e a não associação dessas atividades na adolescência com o excesso de peso na infância indicam a necessidade de intervenções para redução de vários comportamentos de risco. O incentivo à prática de atividade física como forma de reduzir os comportamentos sedentários e consequentemente o excesso de peso entre os jovens torna-se fundamental.

Power producers trading electricity in both pool and forward markets

The electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. This article addresses the challenge of maximizing the profit (or return) of power producers through the optimization of their share of customers. Power producers have fixed production marginal costs and decide the quantity of energy to sell in both day-ahead markets and a set of target clients, by negotiating bilateral contracts involving a three-rate tariff. Producers sell energy by considering the prices of a reference week and five different types of clients with specific load profiles. They analyze several tariffs and determine the best share of customers, i.e., the share that maximizes profit. © 2014 IEEE.

Demux devices based on A-SiC:H

In this paper we present results about the functioning of a multilayered a-SiC:H heterostructure as a device for wavelength-division demultiplexing of optical signals. The device is composed of two stacked p-i-n photodiodes, both optimized for the selective collection of photogenerated carriers. Band gap engineering was used to adjust the photogeneration and recombination rates profiles of the intrinsic absorber regions of each photodiode to short and long wavelength absorption and carrier collection in the visible spectrum. The photocurrent signal using different input optical channels was analyzed at reverse and forward bias and under steady state illumination. This photocurrent is used as an input for a demux algorithm based on the voltage controlled sensitivity of the device. The device functioning is explained with results obtained by numerical simulation of the device, which permit an insight to the internal electric configuration of the double heterojunction.These results address the explanation of the device functioning in the frequency domain to a wavelength tunable photocapacitance due to the accumulation of space charge localized at the internal junction. The existence of a direct relation between the experimentally observed capacitive effects of the double diode and the quality of the semiconductor materials used to form the internal junction is highlighted.

The cardinal of various monoids of transformations that preserve a uniform partition

In this paper we give formulas for the number of elements of the monoids ORm x n of all full transformations on it finite chain with tun elements that preserve it uniform m-partition and preserve or reverse the orientation and for its submonoids ODm x n of all order-preserving or order-reversing elements, OPm x n of all orientation-preserving elements, O-m x n of all order-preserving elements, O-m x n(+) of all extensive order-preserving elements and O-m x n(-) of all co-extensive order-preserving elements.

A importância da liderança para o engagement dos colaboradores nas empresas do Vale do Ave

Dissertação apresentada ao Instituto Politécnico do Porto para obtenção do Grau Mestre em Gestão das Organizações, Ramo de Gestão de Empresas Orientada pela Professora Doutora Maria Alexandra Pacheco Ribeiro da Costa

Desenho universal para a aprendizagem: construindo práticas pedagógicas inclusivas

O presente artigo tem como objetivo apresentar uma grelha de planificação da intervenção facilitadora do desenvolvimento de práticas pedagógicas inclusivas. Para o efeito, procedeu-se a uma revisão da literatura centrada nos conceitos de Educação Inclusiva e de Desenho Universal para a Aprendizagem (Universal Design for Learning), a qual permitiu identificar e fundamentar a pertinência das dimensões a considerar na planificação da intervenção pedagógica, de modo a assegurar o acesso, a participação e o sucesso de todos os alunos. Com a apresentação da grelha de planificação da intervenção pedagógica pretende-se, em última análise, sublinhar a necessidade e a importância de desenvolver processos de planificação que disponibilizem formas diversificadas de motivação e envolvimento dos alunos, que equacionem múltiplos processos de apresentação dos conteúdos a aprender e, por último, que possibilitem a utilização de diversas formas de ação e expressão por parte dos alunos.

Património paleontológico do Concelho de Almada

Pela sua grande riqueza paleontológica, sobretudo no que diz respeito a fósseis miocénicos,as arribas litorais e ribeirinhas do Concelho de Almada merecem ser incluídas no Património Paleontológico Português, de acordo com critérios científicos, pedagógicos e culturais, entre outros. Enumeram-se razões justificativas dessa inclusão, para algumas jazidas seleccionadas, consideradas mais representativas da totalidade do conjunto.