Salt content in bread and dough from northern Portugal: method development and comparison

In the initial stage of this work, two potentiometric methods were used to determine the salt (sodium chloride) content in bread and dough samples from several cities in the north of Portugal. A reference method (potentiometric precipitation titration) and a newly developed ion-selective chloride electrode (ISE) were applied. Both methods determine the sodium chloride content through the quantification of chloride. To evaluate the accuracy of the ISE, bread and respective dough samples were analyzed by both methods. Statistical analysis (0.05 significance level) indicated that the results of these methods did not differ significantly. Therefore the ISE is an adequate alternative for the determination of chloride in the analyzed samples. To compare the results of these chloride-based methods with a sodium-based method, sodium was quantified in the same samples by a reference method (atomic absorption spectrometry). Significant differences between the results were verified. In several cases the sodium chloride content exceeded the legal limit when the chloride-based methods were used, but when the sodium-based method was applied this was not the case. This could lead to the erroneous application of fines and therefore the authorities should supply additional information regarding the analytical procedure for this particular control.

Monte Carlo simulation of the basic features of the GE Millennium MG single photon emission computed tomography gamma camera

Objective - To describe and validate the simulation of the basic features of GE Millennium MG gamma camera using the GATE Monte Carlo platform. Material and methods - Crystal size and thickness, parallel-hole collimation and a realistic energy acquisition window were simulated in the GATE platform. GATE results were compared to experimental data in the following imaging conditions: a point source of 99mTc at different positions during static imaging and tomographic acquisitions using two different energy windows. The accuracy between the events expected and detected by simulation was obtained with the Mann–Whitney–Wilcoxon test. Comparisons were made regarding the measurement of sensitivity and spatial resolution, static and tomographic. Simulated and experimental spatial resolutions for tomographic data were compared with the Kruskal–Wallis test to assess simulation accuracy for this parameter. Results - There was good agreement between simulated and experimental data. The number of decays expected when compared with the number of decays registered, showed small deviation (≤0.007%). The sensitivity comparisons between static acquisitions for different distances from source to collimator (1, 5, 10, 20, 30cm) with energy windows of 126–154 keV and 130–158 keV showed differences of 4.4%, 5.5%, 4.2%, 5.5%, 4.5% and 5.4%, 6.3%, 6.3%, 5.8%, 5.3%, respectively. For the tomographic acquisitions, the mean differences were 7.5% and 9.8% for the energy window 126–154 keV and 130–158 keV. Comparison of simulated and experimental spatial resolutions for tomographic data showed no statistically significant differences with 95% confidence interval. Conclusions - Adequate simulation of the system basic features using GATE Monte Carlo simulation platform was achieved and validated.

Factors associated with depression symptoms in high school students in São Paulo, Brazil

OBJECTIVE: To assess factors associated with depression symptoms in high school students. METHODS: A cross-sectional study involving high school students was conducted in the city of São Paulo, Brazil, 2001. A total of 724 students aged 14-18 years answered questionnaires on life and health conditions. Another questionnaire was applied to working (44.8%) and unemployed (22.9%) students to collect information on working conditions. Factors associated to depressive disorders were analyzed using multiple logistic regression controlled for occupational status. RESULTS: Overall prevalence rate of depression was 7.5%. Rates according to gender were 39 (10.3%) in females and 15 (4.3%) in males. The multiple logistic regression analysis showed that factors associated with depressive disorders were: poor self-perception of health (OR=5.78), being female (OR = 2.45), and alcohol consumption (OR=2.35). CONCLUSIONS: The study results showed that sociodemographic, lifestyle and health variables were associated with symptoms of depression in this population. These ndings suggest that it is important to have mental health professionals available in high schools for early detection of mental conditions and student counseling.

Violência sexual e associação com a percepção individual de saúde entre mulheres gestantes

OBJETIVO: Estimar a prevalência de histórico de violência sexual entre mulheres gestantes e sua associação com a percepção de saúde. MÉTODOS: Estudo transversal, com 179 mulheres maiores de 14 anos e grávidas de 14 a 28 semanas, entrevistadas em serviços públicos de saúde em São Paulo, SP, entre os anos de 2006 e 2007. Os instrumentos utilizados foram: inventário de violência sexual, inventário de dados sociodemográficos e questionário de qualidade de vida relacionada à saúde: "Medical Outcomes 12-Item Short-Form Health Survey" (SF-12®). Mulheres com e sem história de violência sexual foram comparadas quanto à idade, escolaridade, ocupação, estado civil, cor da pele e autopercepção de saúde física e mental. A violência sexual foi caracterizada em penetrativa ou não penetrativa. RESULTADOS: Houve prevalência de 39,1% de violência sexual entre as entrevistadas, sendo 20% do tipo penetrativo, cometida sobretudo por agressores conhecidos. Em 57% das mulheres a primeira agressão ocorreu antes dos 14 anos. Não houve diferenças sociodemográficas entre mulheres que sofreram e as que não sofreram violência sexual. Escores médios de percepção de saúde física entre as entrevistadas com antecedente de violência sexual foram menores (42,2; DP=8,3) do que das mulheres sem este antecedente (51,0; DP=7,5) (p<0,001). A percepção de saúde mental teve escore médio de 37,4 (DP=11,2) e 48,1 (DP=10,2) (p<0,001), respectivamente para os dois grupos. CONCLUSÕES: Houve alta prevalência de violência sexual entre as grávidas dos serviços de saúde avaliados. Mulheres com antecedente de violência sexual apresentaram pior percepção de saúde do que as sem esse antecedente.

Sulfadiazine-potentiometric sensors for flow and batch determinations of sulfadiazine in drugs and biological fluids

New PVC membrane electrodes for the determination of sulfadiazine (SDZ) are presented. The electrodes are fabricated with conventional and tubular configurations with a graphite-based electrical contact, and no internal reference solution. The selective membranes consist of bis(triphenylphosphoranilidene)ammonium·SDZ (electrode A), tetraoctylammonium bromide (electrode B), or iron(II)-phthalocyanine (FePC) (electrode C) electroactive materials dispersed in a PVC matrix of o-nitrophenyl octyl ether (o-NPOE) plasticizer. The sensors A, B, and C displayed linear responses over the concentration ranges 1.0*10-2 – 1.0*10–5, 1.0*10–2 – 7.5*10–6, and 3.2*10–2 – 7.0* 10–6 mol l–1 (detection limits of 1.09, 2.04 and 0.87 mg ml–1) with anionic slopes of –57.3 ± 0.1, –46.7 ± 0.5, and –65.1 ± 0.2 mV decade–1, respectively. No effect from pH was observed within 4.0 – 5.5, 4.8 – 10, and 4.5 – 8, respectively, and good selectivity was found. The sensors were applied to the analysis of pharmaceuticals and biological fluids in steady state and in flow conditions.

Electrochemical oxidation of propanil and related N-substituted amides

The electrochemical behaviour of propanil and related N-substituted amides (acetanilide and N,N-diphenylacetamide) was studied by cyclic and square wave voltammetry using a glassy carbon electrode. Propanil has been found to have chemical stability under the established analytical conditions and showed an oxidation peak at +1.27V versus Ag/AgCl at pH 7.5. N,N-diphenylacetamide has a higher oxidation potential than the other compounds of +1.49V versus Ag/AgCl. Acetanilide oxidation occurred at a potential similar to that of propanil, +1.24V versus Ag/AgCl. These results are in agreement with the substitution pattern of the nitrogen atom of the amide. A degradation product of propanil, 3,4-dichloroaniline (DCA), was also studied, and showed an oxidation peak at +0.66V versus Ag/AgCl. A simple and specific quantitative electroanalytical method is described for the analysis of propanil in commercial products that contain propanil as the active ingredient, used in the treatment of rice crops in Portugal.

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.

Human risk assessment of benzene after a gasoline station fuel leak

OBJECTIVE: To assess the health risk of exposure to benzene for a community affected by a fuel leak. METHODS: Data regarding the fuel leak accident with, which occurred in the Brasilia, Federal District, were obtained from the Fuel Distributor reports provided to the environmental authority. Information about the affected population (22 individuals) was obtained from focal groups of eight individuals. Length of exposure and water benzene concentration were estimated through a groundwater flow model associated with a benzene propagation model. The risk assessment was conducted according to the Agency for Toxic Substances and Disease Registry methodology. RESULTS: A high risk perception related to the health consequences of the accident was evident in the affected community (22 individuals), probably due to the lack of assistance and a poor risk communication from government authorities and the polluting agent. The community had been exposed to unsafe levels of benzene (> 5 µg/L) since December 2001, five months before they reported the leak. The mean benzene level in drinking water (72.2 µg/L) was higher than that obtained by the Fuel Distributer using the Risk Based Corrective Action methodology (17.2 µg/L).The estimated benzene intake from the consumption of water and food reached a maximum of 0.0091 µg/kg bw/day (5 x 10-7 cancer risk per 106 individuals). The level of benzene in water vapor while showering reached 7.5 µg/m3 for children (1 per 104 cancer risk). Total cancer risk ranged from 110 to 200 per 106 individuals. CONCLUSIONS: The population affected by the fuel leak was exposed to benzene levels that might have represented a health risk. Local government authorities need to develop better strategies to respond rapidly to these types of accidents to protect the health of the affected population and the environment.

Gender and racial inequalities in trends of oral cancer mortality in Sao Paulo, Brazil

OBJECTIVE:To analyse recent trends in oral cancer mortality, focusing specifically on differences concerning gender and race.METHODS:Official information on deaths and population in the city of Sao Paulo, 2003 to 2009, were used to estimate mortality rates from oral cancer (C00 to C10, International Classification of Diseases, 10th Revision), adjusted for age and stratified by gender (females and males) and race (blacks and whites). The Prais-Winsten auto-regression procedure was used to analyse the time series.RESULTS:During the study period, 8,505 individuals living in the city of Sao Paulo died of oral cancer. Rates increased for females (rate of yearly increase = 4.4%, 95%CI 1.4;7.5), and levelled off for men, which represents an inversion of previous trends among genders in the city. Increases were identified for blacks, with a high rate of yearly increase of 9.1% (95%CI 5.5;12.9), and levelled off for whites. Oral cancer mortality in blacks almost doubled during the study period, and surpassed mortality in whites for almost all categories.CONCLUSIONS:Mortality presented a higher increase among women than in men, and it doubled among backs. The surveillance of trends of oral cancer mortality across gender and racial groups may contribute to implementing socially appropriate health policies, which concurrently reduce the burden of disease and the attenuation of unfair, avoidable and unnecessary inequalities in health.

Letalidade e internações de pacientes em hemodiálise em plano de saúde

OBJETIVO: Analisar desfechos clínicos de pacientes incidentes em hemodiálise vinculados a operadora de plano de saúde.MÉTODOS: Estudo de coorte de incidentes em hemodiálise em Belo Horizonte, MG, de 2004 a 2008, a partir de registros no banco de dados de operadora de planos de saúde. Variáveis independentes: sexo, idade, tempo entre primeira consulta com nefrologista e início da hemodiálise, tipo do primeiro acesso vascular, diabetes mellitus, tempo de permanência hospitalar/ano de tratamento e óbito. Variáveis dependentes: tempo entre início da hemodiálise e óbito e tempo de permanência hospitalar/ano de tratamento > 7,5 dias. Análise estatística: teste Qui-quadrado de Pearson na análise univariada para os desfechos óbito e tempo de permanência hospitalar/ano de tratamento; método de Kaplan-Meier para análise de sobrevida; modelo de Cox e regressão Poisson para risco de óbito e chance de tempo de permanência hospitalar/ano de tratamento > 7,5 dias. Foi utilizada ferramenta de Business Intelligence para extração dos dados e software Stata(r) 10.0.RESULTADOS: Estudados 311 indivíduos em hemodiálise, 55,5% homens, média de 62 anos (dp: 16,6 anos). A prevalência aumentou 160% no período estudado. Na análise de sobrevivência a mortalidade foi maior entre os mais idosos, nos que não realizaram consulta com nefrologista, fizeram uso de cateter vascular temporário como primeiro acesso, com diabetes mellitus, nos que foram internados no mesmo mês do início da hemodiálise. No modelo de Cox associaram-se a maior risco para óbito a idade avançada, diabetes mellitus, não realizar consulta prévia com nefrologista e internar-se no primeiro mês de hemodiálise. Maior tempo de permanência hospitalar/ano de tratamento não se associou ao sexo e diabetes. As variáveis não foram significativas na regressão Poisson.CONCLUSÕES: A avaliação pelo especialista antes do início da hemodiálise diminui o risco de óbito na doença renal crônica terminal, enquanto o diabetes e internação no mesmo mês de início da hemodiálise são marcadores de risco para o óbito.

Avaliação terapêutica do praziquantel (Embay 8440) na infecção humana pelo S. mansoni

Foram tratados com praziquantel, dose oral única de 40 ou 50 mg/kg, 200 indivíduos portadores de esquistossomose mansoni, matriculados na Clínica de Doenças Infecciosas e Parasitárias do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. As idades dos pacientes variavam de seis a 63 anos, sendo que 33 (16,5%) eram menores de 15 anos. Os principais efeitos colaterais consistiram em tontura 27,5%; sonolência 21,0%; eólica 17,5%; náusea 16,0%; diarréia 9,0%; cefaléia 7,5%; vômito 4,0%; febre 2,0%; disenteria 1,0%; tremor 1,0%; exantema 1,0% e urticaria 0,5%. A toxicidade do medicamento foi investigada mediante a realização, pré e pós-tratamento, de exames hematimétricos, bem como de função renal (uréia e creatinina), hepática (enzimas de liberação hépato-canalicular e bilirrubinas), cardíaca (ECG) e neuropsiquiátrica (EEG). Não foram encontradas nesses controles alterações relevantes que repercutissem clinicamente. O controle de cura verificou-se em 115 indivíduos, através de oito coproscopias, no período de seis meses, subseqüente ao tratamento, utilizando-se duas técnicas (HOFFMAN e KATO/KATZ) para cada amostra de fezes. Dos 82 indivíduos que tiveram as oito coproscopias negativadas, 62 realizaram biópsia retal. Essa mostrou-se positiva em duas oportunidades, indicando um percentual de 3,2% de achados falsos negativos com relação às coproscopias. Os índices de cura variaram de 65,2%, nos pacientes menores de 15 anos, a 75% nos acima dessa idade. Para todas as faixas etárias a eficácia foi de 71,3%. Os resultados obtidos demonstram ter o praziquantel, nas doses empregadas, relativa eficácia no tratamento da esquistossomose mansoni, bem como ser determinante de baixos efeitos tóxico-colaterais.

Drilling damage in composite material

The characteristics of carbon fibre reinforced laminates have widened their use from aerospace to domestic appliances, and new possibilities for their usage emerge almost daily. In many of the possible applications, the laminates need to be drilled for assembly purposes. It is known that a drilling process that reduces the drill thrust force can decrease the risk of delamination. In this work, damage assessment methods based on data extracted from radiographic images are compared and correlated with mechanical test results—bearing test and delamination onset test—and analytical models. The results demonstrate the importance of an adequate selection of drilling tools and machining parameters to extend the life cycle of these laminates as a consequence of enhanced reliability.

Estudo de novos centros contendo ferro: isolamento e caracterização de proteínas de desulfovibrio desulfuricans ATCC 27774

Dissertação apresentada para obtenção do Grau de Doutor em Bioquímica, pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

Avaliação do funcionamento da ETAL do aterro sanitário de vila Ruiva e proposta de reabilitação

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Sanitária

Efficacy of oxamniquine, praziquantel and a combination of both drugs in schistosomiasis mansoni in Brazil

A randomized clinical trial was carried out to compare the efficacy of a low-dosage combination of oxamniquine (7.5 mg/kg) plus praziquantel (20 mg/kg) against either agent, oxamniquine (15 mg/kg) or praziquantel (40 mg/kg) alone, in the treatment of schistosomiasis mansoni in the Brazilian north-east. The drugs were randomly administered per os to 91 patients. Six and twelve months after treatment 89% of those admitted to the trial were reexamined by Kato-Katz method (ten slides) and MIF technique (one gram of stool) The achieved cure rates, as defined by absence of S. mansoni eggs in the faeces of individual patients at all points during the parasitological follow-up, were 81.8%, 81.2% and 67.6% for praziquantel, oxamniquine and the combination respectively. The reduction of eggs excretion in non cured patients six months after therapy ranged from 93.8-96.8% with praziquantel, 32.5-97% with oxamniquine and 76.9-99.5% with the combination. It is concluded that, at the used dosages, the three therapeutical regimens give similar and satisfactory results in the treatment of uncomplicated S. mansoni infection in Brazil.