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In the present research, a new technology using the application of ozone (O³) together with an ultrafiltration (UF) membrane was tested for the tertiary treatment of wastewater. The primary and secondary wastewater-treatment systems were a septic tank and anaerobic filter. The experiment was divided into two stages: the first including only the application of O3 in the reactor, and the second, inclusion of the UF membrane. During the first stage of the study, where only the ozone was applied, a time of 40 min was chosen, with removal levels for chemical oxygen demand (COD), five-day biochemical oxygen demand (BOD5), total organic carbon (TOC), turbidity and ammonium (NH4+) of 39.5%, 45.4%, 32.4%, 44.85% and 68.4% being recorded. During stage 2, the UF membrane inside the reactor was activated after 40 min of ozonation. The values for the removal of COD, BOD5, TOC, turbidity, NH4+ and total phosphorus were 89.13%, 95.41%, 82%, 93.4%, 14.75% and 79.67%, respectively. The use of O3 + UF removed 100% of total coliforms and viruses from the secondary wastewater. In accordance with North American and European guidelines, the water resulting from the treatment process is fit for reuse. The operating costs can vary between 0.859 € m-3 and 2.440 € m-3 depending on the cost per kWh in each country. The experiments were conducted under batch-mode conditions, further evaluations about the real scale operation would require a previous pilot stage that would develop more tools for operations specifications and their costs. The results recorded here show that the performance of this new reactor design is effective in the tertiary treatment of wastewater, and should be available for use in the near future.

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Chemical oxidation was applied to an artificially contaminated soil with naphthalene (NAP). Evaluation of NAP distribution and mass reduction in soil, water and air phases was carried out through mass balance. Evaluation of NAP distribution and mass reduction in soil, water and air phases was carried out through mass balance. The importance of the air phase analysis was emphasized by demonstrating how NAP behaves in a sealed system over a 4 hr reaction period. Design of Experiments method was applied to the following variables: sodium persulfate concentration [SP], ferrous sulfate concentration [FeSO4], and pH. The system operated with a prefixed solid to liquid ratio of 1:2. The following conditions resulted in optimum NAP removal [SP] = 18.37 g/L, [FeSO4] = 4.25 g/L and pH = 3.00. At the end of the 4 hr reaction, 62% of NAP was degraded. In the soil phase, the chemical oxidation reduced the NAP concentration thus achieving levels which comply with Brazilian and USA environmental legislations. Besides the NAP partitioning view, the monitoring of each phase allowed the variabilities assessment over the process, refining the knowledge of mass reduction. Based on NAP distribution in the system, this study demonstrates the importance of evaluating the presence of semi-volatile and volatile organic compounds in the air phase during remediation, so that there is greater control of the system as to the distribution and presence of the contaminant in the environment. The results highlight the importance of treating the contaminant in all its phases at the contaminated site.

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The present study reports on the remediation of an effluent from the wood-laminate industry using Pleurotus ostreatus EB 016 in combination with photo-Fenton oxidation. Fermentation of the effluent with P. ostreatus EB-016 was carried out in agitated flasks to evaluate the influence of pH, and concentrations of carbon and nitrogen sources by a multivariate approach. Subsequently, bioassays was conducted in an air-lift bioreactor using the pre-optimized conditions. In addition, photo-Fenton oxidative treatment was employed to degrade recalcitrant compounds, and the ecotoxicity of the effluents were evaluated using Escherichia coli as a biological model. The crude effluent presented high contents of total phenolics (1,220 mg/L), solids (18.45 g/L) and color intensity (8,333 CU), besides high values of chemical (COD 2,477 mg O2./L) and biochemical (BOD5, 8,450 mg O2/L) oxygen demand. Another feature was the high inhibition on Escherichia coli (71%). Reduction of 64% COD was obtained under optimized conditions (pH5.7, 7.5 g/L sucrose, 4.0 g/L ammonium nitrate) in agitated flasks after 10 days treatment. In the air-lift reactor, 50.6% COD and 29.9% total phenols were removed after 10 days. Combination of biotreatment with photo-Fenton oxidation resulted in removal of 99.2% COD and 92.2% phenolics and absence of inhibition on Escherichia coli.

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Antecedentes: el consumo de frituras en México es alto, aunque las grasas se asocian con enfermedades crónicas no transmisibles. Objetivo: evaluar la composición química y calidad de la grasa obtenida de churros fritos de maíz elaborados y consumidos en Navojoa, estado de Sonora, México. Materiales y métodos: a cuatro muestras obtenidas en establecimientos comerciales se les realizó análisis químico proximal y determinación de índices de calidad de la grasa (acidez, peróxidos, yodo y anisidina), según normas mexicanas. Resultados: el aporte nutricional de las muestras estuvo en los siguientes rangos expresados en g %: grasas (23,7±0,2 y 35,2±1,0 g %), proteínas (2,5±0,0 y 8,1±1,4 g %), carbohidratos (54,1±0,3 y 64,40±0,5 g %) y energía (485±3 y 531±1 kcal %) con diferencias entre ellas (p<0,05). El mayor contenido de grasa y energía lo presentó B2 y el mejor perfil nutricional B4. La muestra B1 superó los límites máximos permitidos de acidez (4,8) y de peroxidación (10,6) con diferencias respecto a las otras muestras (p<0,05). Conclusiones: la densidad energética de los churros de maíz analizados es alta (superior a 4 kcal/g) al igual que el aporte de grasas, especialmente en la muestra B2. B4 presenta el mejor perfil nutricional y B1 el mayor deterioro oxidativo.

Background: Consumption of fried foods in Mexico is high, even though fats in fried foods are associated with noncommunicable chronic diseases. Objective: Evaluate the chemical composition and fat quality obtained from fried corn churros prepared and consumed in Navojoa, state of Sonora, Mexico. Materials and Methods: Four samples obtained from commercial establishments were subjected to proximal chemical analysis and determination of fat quality indices (acidity, alkalinity, iodine and anisidine), according to Mexican standards. Results: The nutritional breakdown of the samples is shown in the following ranges, expressed as grams % (g %): fats (23.7 ± 0.2 and 35.2 ± 1.0 g %), proteins (2.5 ± 0.0 and 8.1 ± 1.4 g %), carbohydrates (54.1 ± 0.3 and 64.4 ± 0.5 g %), and energy (kcal) (485 ± 3 and 531 ± 1) with significant differences between samples (p<0.05). The highest fat and energy content was presented by sample B2 and the best nutritional profile by sample B4. Sample B1 exceeded the maximum limits of acidity (4.8) and alkalinity (10.6) with a significant inter-sample difference (p <0.05). Conclusion: The energy density of the sampled fried corn churros is high (above 4 kcal/gram), as well as the fat content, especially in sample B2. Sample B4 presents the best nutrition profile and sample B1 the greatest oxidative deterioration.

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Abstract The effect of third and second-generation type of beta-blocker on substrate oxidation especially during high-intensity exercises are scarce. The objective of the study is to explore differences of beta-blocker regimens (vasodilating vs. non-vasodilating beta-blockers) for substrate oxidation during in high-intensity intermittent exercise (HIIE) in chronic heart failure and reduced ejection fraction (HFrEF). Eighteen CHF males (58.8 ± 9 years), 8 under use of β1 specific beta-blockers+alfa 1-blocker and 10 using β1 non-specific beta-blockers, were randomly assigned to 4 different HIIE, in a cross-over design. The 4 protocols were: 30 seconds (A and B) or 90 seconds (C and D) at 100% peak power output, with passive (A and C) or active recovery (50% of PPO; B and D). Energy expenditure (EE; kcal/min), quantitative carbohydrate (CHO) and lipid oxidation (g/min) and qualitative (%) contribution were calculated. Two-way ANOVA and Bonferroni post-hoc test were used (p-value ≤ 0.05) to compare CHO and lipid oxidation at rest and at 10min. Total exercise time or EE did not show differences for beta-blocker use. The type of beta-blocker use showed impact in CHO (%) and lipid (g/min and %) for rest and 10 min, but absolute contribution of CHO (g/min) was different just at 10min (Interaction p = 0.029). Higher CHO oxidation was found in vasodilating beta-blockers when comparing to non-vasodilating. According to our pilot data, there is an effect of beta-blocker type on substrate oxidation during HIIE, but no influence on EE or exercise total time in HFrEF patients.

Resumo Os dados sobre efeito do tipo de betabloqueador de terceira e segunda geração na oxidação do substrato, especialmente durante exercícios de alta intensidade, são escassos. O objetivo do estudo é explorar as diferenças de tratamentos com betabloqueadores (betabloqueadores vasodilatadores vs. não-vasodilatadores) na oxidação de substratos durante exercícios intermitentes de alta intensidade (HIIE) na insuficiência cardíaca crônica e fração de ejeção do ventrículo esquerdo reduzida (ICFEr). Dezoito pacientes do sexo masculino com ICC (58,8 ± 9 anos), 8 em uso de betabloqueadores β1 específicos + bloqueador α-1 e 10 utilizando betabloqueadores β1 não-específicos, foram aleatoriamente designados para 4 diferentes HIIE, em um desenho cruzado. Os 4 protocolos foram: 30 segundos (A e B) ou 90 segundos (C e D) a 100% da potência de pico de saída (PPO), com recuperação passiva (A e C) ou ativa (50% de PPO; B e D). O gasto energético (GE; kcal/min), a ingestão de carboidratos quantitativos (CHO) e oxidação lipídica (g/min) e qualitativa (%) foram calculados. Anova de dois fatores e teste post-hoc de Bonferroni foram usados (p-valor ≤ 0,05) para comparar a oxidação de CHO e lipídios em repouso e aos 10 minutos. O tempo total de exercício ou GE não mostraram diferenças de acordo com o uso de betabloqueadores. O tipo de betabloqueador mostrou impacto em CHO (%) e lípides (g/min e %) para repouso e aos 10 min, mas a contribuição absoluta de CHO (g/min) foi diferente apenas aos 10 minutos (Interação p = 0,029). Foram encontradas maiores oxidações de CHO com betabloqueadores vasodilatadores quando comparados com os não-vasodilatadores. De acordo com nossos dados piloto, há um efeito do tipo do betabloqueador na oxidação do substrato durante o HIIE, mas nenhuma influência no GE ou no tempo total de exercício nos pacientes com ICFEr.

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Polycyclic aromatic hydrocarbons (PAH) are neutral, nonpolar and hydrophobic molecules that tend to sorb onto soil organic matter. Chemical oxidation is a good choice to avoid the limitations of bioremediation. To evaluate the efficiency of different types of oxidation (permanganate, hydrogen peroxide, and persulfate) and activation (heat, alkaline, and iron), batch reactors were prepared. The soil was contaminated with phenanthrene and pyrene (1200 ± 200 and 2800 ± 100mg per kg of dry soil, respectively) and aged for fifteen months. Treatments were prepared with 10g of contaminated dry soil and 20ml of water and incubated at room temperature for 7 days. Analyses of phenanthrene and pyrene concentrations, soil pH and electric conductivity were performed. Counts of heterotrophic cultivable bacteria on R2A medium and PAH-degraders were carried out after 7 days of treatment. The persulfate treatment at room temperature, without the addition of activators, achieved better results than treatments with the same doses of permanganate or hydrogen peroxide. All the strategies to improve persulfate treatments yielded higher degradation of pyrene than the biological control, as expected from the structural description of this compound by Clar's model. The thermal activation of persulfate (65°C for 6h) led to the degradation of more than 90% of both PAHs after 7 days of treatment.

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RESUMO Este artigo busca consolidar as principais características, vantagens e desvantagens de métodos disponíveis no meio técnico e científico para o controle de odores e corrosão em redes coletoras e estações de tratamento de esgoto, trazendo uma abordagem atualizada sobre soluções preventivas relacionadas à concepção e à operação de sistemas de esgotamento, com adição de compostos químicos ou aeração em fase líquida. São apresentados os princípios de cada técnica e consolidadas as principais diretrizes para o projeto de alternativas. Além disso, são apresentadas diretrizes para a concepção de soluções corretivas com contenção e exaustão de unidades/fontes potencialmente odorantes, incluindo uma discussão sobre os processos atualmente disponíveis no meio técnico-científico para tratamento de gases odorantes e corrosivos.

ABSTRACT This paper aims to consolidating the main characteristics, advantages and disadvantages of available methods in technical-scientific community to odor and corrosion control in sanitary sewerage systems and treatment plants, taking along an innovative approach on preventive solutions related to sewage systems design and operation with addition of chemicals or liquid phase aeration. The main beliefs of each technique are presented as well as the main guidelines for alternatives design. In addition, guidelines are given for corrective solutions design of covers and exhaust of potentially odorous sources, as well as a brief discussion of processes currently available in the technical-scientific community to the treatment of odorant odorous and corrosive gases.