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Nitrification is a biochemical process that allows oxidation of ammonium ion to nitrite, and nitrite to nitrate in a system. Aerobic processes, such as use of submerged biological aerated filter (SBAF), enable nitrification. However, some variables that are entirely unavailable or not available at the required concentration range may hamper the process. In this study, nitratation under high dissolved oxygen (DO) concentrations was evaluated in laboratory-scale bioreactors containing 10% inoculum (0.5 kg kg-1) fed with affluent from a SBAF that receive the sewage generated from washing the bays of a dog kennel. The following variables were monitored over time: ammoniacal nitrogen (12.44-29.62 mg L-1), nitrite (0.28-0.54 mg L-1), nitrate (1.75-3.55 mg L-1), pH (8.11 ± 0.62), temperature (21.61 ± 1.24°C) and DO (9.69 ± 0.36 mg L-1). Quantification of nitrifying bacteria by the multiple tube technique showed the value of 1.4 × 1012 MPN mL-1for ammonia-oxidizing bacteria (AOB) and 9.2 × 1014 MPN mL-1 for nitrite-oxidizing bacteria. These values were higher than those found in a synthetic medium, which can be explained by the greater availability of ammonium and nitrite in the effluent. By the extraction of genomic DNA, and PCR, with specific primers, the presence of the AmoA (Ammonia monooxygenase) gene for AOB and of the Nitrobacter was detected in the bioreactor samples. By PCR-DGGE, the sequenced bands showed high similarity with denitrifying bacteria, such as Pseudomonas, Limnobacter, Thauera, Rhodococcus, and Thiobacillus. Thus, the saturation of dissolved oxygen in the system resulted in improvement in the nitratation step and allowed detection of bacterial genera involved in the process.

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Trichloroethylene (TCE) is a carcinogenic compound that is commonly present in groundwater and has been detected in drinking water sources for Mexican towns in the Mexico-US border area. Nitrifying bacteria, such as Nitrosomonas europaea, have been shown to be capable of degrading halogenated compounds, including TCE, but it is difficult to obtain high cell concentrations of these bacteria. The aim of the present study was to generate biomass of a nitrifying bacterial consortium from the sludge of an urban wastewater treatment plant (WWTP) and evaluate its capacity to biodegrade TCE in two different natural lab-scaled packed bed bioreactors. The consortium was isolated by a novel method using a continuous stirred-tank bioreactor inoculated with activated sludge from the Domos WWTP located in Cd. Obregón, Sonora, Mexico. The bioreactor was fed with specific media to cultivate ammonia-oxidizing bacteria at a dilution rate near the maximum specific growth rate reported for Nitrosomonas europaea. Optical density and suspended solids measurements were performed to determine the culture biomass production, and the presence of inorganic nitrogen species was determined by spectrophotometry. The presence of nitrifying ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) was confirmed by PCR amplification, and biofilm formation was observed by scanning electron microscopy. Batch-scale experiments confirmed the biodegradative activity of the isolated consortium, which was subsequently fixed in an inorganic carrier as zeolite and a synthetic carrier such as polyurethane to both be used as lab-scale packed-bed bioreactors, with up to 58.63% and 62.7% of TCE biodegradation achieved, respectively, demonstrating a possible alternative for TCE bioremediation in environmental and engineering systems.

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Esse artigo objetiva fazer um panorama do financiamento da política de assistência social, apresentando as mudanças normativas, o aporte orçamentário e as perspectivas. Como metodologia, acessou-se o levantamento da produção normativa do órgão gestor da política, que pode ser solicitado aos autores, e a análise descritiva dos dados extraídos do Painel de Orçamento Federal, do atual Ministério da Economia1 , que são oriundos do Sistema Integrado de Administração Financeira do Governo Federal (SIAFI), sistema que realiza toda a execução orçamentária e financeira do governo federal. Os resultados apontam para mudanças, com base nas orientações da Política Nacional de Assistência Social (PNAS) e da Norma Operacional Básica (NOBs/SUAS), que propiciaram um novo padrão de financiamento, com adensamento da institucionalidade, maior abrangência territorial e populacional e ampliação do escopo protetivo da política. O trajeto orçamentário foi ascendente, saindo de um patamar de 0,9% do Produto Interno Bruto (PIB), em 2006, para 1,3%, em 2018. As perspectivas, porém, não são nada animadoras, tendo em vista o cenário de congelamento, em termos reais, da despesa primária da União e um fortalecimento da concepção de assistência social como caridade e benemerência.

This article aims to give an overview of the financing of social assistance policy, presenting the normative changes, the budget contribution, and the perspectives. As a methodology, it was accessed the survey of the normative production of the policy management body, which can be requested from the authors, and the descriptive analysis of the data extracted from the Federal Budget Panel of the current Ministry of Economy, which come from the Integrated System of Financial Administration of the Federal Government (SIAFI), system that performs all the budgetary and financial execution of the federal government. The results point to changes, based on the guidelines of the National Social Assistance Policy (PNAS) and the Basic Operational Standard (NOBs / SUAS), which provided a new standard of financing, with a broader institutional and territorial scope and expansion of the policy's protective scope. The budget line went up from 0.9% of gross domestic product (GDP) in 2006 to 1.3% in 2018. The outlook, however, is not encouraging, considering the scenario of freezing the Union's primary expenditure in real terms and strengthening the concept of social assistance as charity and benevolence.

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Abstract Currently, nitrogen has become the main element of water pollution, causing riverine, lacustrine and coastal eutrophication. The continuous contamination of aquifers and the absence of planned water resource utilization, boost its scarcity, and has been the only way in which our societies become aware of the urgent need to process the generated wastewater. The objective of this research was to evaluate the nitrifying capacity of different autochthonous bacterial isolates from soils from nearby sources of domestic wastewater drainage. For this, bacteria were isolated from Pirro River, contaminated with nitrogen of domestic sewage. Nitrifying bacteria were counted by serial dilution and agar plates, and were isolated until obtaining axenic colonies. These were identified by biochemical batteries or genetic sequencing, and the quantification of their nitrifying capacity was obtained by the methods 4500- NH4 + -F and 4500-NO-2-B, all between September 26, 2011 and March 16, 2014. A total of seven strains of nitrifying microorganisms were isolated and purified, including four Streptomyces sp., one Pseudomonas putida, one Sphingomonas sp. and one Aeromonas sp. We found that there were 2.23 x 105 UFC/g of soil of ammonium oxidizing bacteria and 2.2 x 104 CFU/g of soil of nitrite oxidizing bacteria in the samples. The quantification of the nitrifying capacity of the strains by colorimetric methods, determined that the maximum ammonium removal capacity was 0.050 mg N/L/day and 0.903 mg N/L/day of nitrite. The collection of few strains of nitrifying organisms and a low CFU count, can be attributed to the technique used, since this only recovers 1 % of the microorganisms present in a sample, which, however, is acceptable for studies which main purpose is to obtain cultivable microorganisms. Future research should consider removal tests with higher ammonium and nitrite levels, to find the maximum capacity of the isolated microorganisms, and evaluate their potential use in wastewater treatment systems.

Resumen El suelo es la matriz fundamental donde suceden las reacciones químicas y biológicas que permiten el desarrollo de la vida en la tierra, y donde ocurren procesos fundamentales como la mineralización de los elementos y la fijación del nitrógeno. Hoy en día el nitrógeno se ha transformado en uno de los principales elementos contaminantes de los cuerpos de agua, causando consecuencias como la eutrofización de ríos, lago y costas. En los ambientes acuáticos, el nitrógeno puede ser encontrado en forma de amonio N-NH4 +, nitritos N-NO2 -o nitratos N-NO3 -, los cuales pueden ser utilizados por las bacterias nitrificantes amonio y nitrito oxidantes y desnitrificantes para su crecimiento y consecuente remoción. Esta investigación se planteó como objetivo evaluar la capacidad nitrificante de diferentes aislamientos bacterianos autóctonos, aislados de suelos cercanos a fuentes de vertido de aguas residuales de tipo doméstico para su potencial uso en sistemas de tratamiento de aguas residuales. Se realizó el recuento de bacterias nitrificantes por la técnica de dilución seriada y siembra en placas de agar mínimo mineral, su aislamiento por repique en placa hasta obtener colonias axénicas, su identificación por medio de baterías bioquímicas o secuenciación genética y la cuantificación de su capacidad nitrificante por los métodos 4500- NH4 +-F y 4500- NO- 2-B, entre el 26/09/2011 y 16/03/2014; las bacterias fueron aisladas de un punto del río Pirro contaminado con nitrógeno de aguas residuales de tipo doméstico. Se lograron aislar y purificar siete cepas de microorganismos nitrificantes entre las que se encuentran cuatro de Streptomyces sp., una de Pseudomonas putida, una de Sphingomonas sp. y una de Aeromonas sp. Se encontró que existen 2.23 x105 UFC/g de suelo de bacterias amonio oxidantes y 2.2 x104 UFC/g de suelo de las nitrito oxidantes. La cuantificación de la capacidad nitrificante de las cepas por medio de los métodos colorimétricos determinó que la capacidad máxima de remoción de amonio es de 0.050 mg N/L/día y la de nitrito en 0.903 mg N/L/día. La obtención de pocas cepas de organismos nitrificantes y un bajo recuento de UFC se puede atribuir a la técnica empleada, ya que esta solo recupera un 1 % de los microorganismos presentes en una muestras, lo cual sin embargo, es aceptable para estudios que tienen como objetivo la obtención de microorganismos cultivables. Se recomienda realizar ensayos de remoción con niveles de amonio y nitrito más altos para hallar la capacidad máxima de los microorganismos aislados.

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O presente trabalho consiste numa revisão da legislação que instituiu e vem modelando o Sistema Único de Saúde (SUS) no Brasil. Seu principal objetivo á analisar o percurso das politicas de saúde e as mudanças ocorridas nas leis desde a implantação do SUS até os dias atuais. O objeto deste trabalho foi uma análise crítica da legislação, além da experiência pessoal do outor na área de gestão.

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Objetivo. Describir la prevalencia de maracadores serológicos de los virus de la hepatitis en una población de embarazadas. Material y métodos. Se estudiaron 1 500 sueros de embarazadas en los que se determinaron: anticuerpos IgG contra el virus de la hepatitis A (anti-VHA); anticuerpos IgG contra el antígeno central del virus de la hepatitis B (ant-HB-c), y su antígeno de superficie (AgsHB); así como anticuerpos contra el virus de la hepatitis C (anti-VHC). En los casos positivos al AgsHB se buscaron anticuerpos contra el virus de la hepatitis D (anti-VHD) y el antígeno e del virus de la hepatitis B (AgeHB). Todas las determinaciones se realizaron por la técnica de ELISA. Resultados. El 93.3 por ciento de los sueros estudiados tuvo anti-VHA IgG positivos. La prevalencia del AgsHB fue del 0.26 por ciento y de anti-VHC del 0.53 por ciento. No hubo pacientes con positividad para anti-VHD ni para el AgeHB. Conclusiones. Se encontró una prevalencia del AgsHB superior a la de otros estudios en embarazadas mexicanas. Consideramos que el escrutinio del AgsHB debe formar parte de los exámenes de control prenatal

Objective. To determine the seroprevalence of hepatitis A, B, C and D virus infection among pregnant women attending a perinatal care hospital. Material and methods. A prospective study was carried out to determine the seroprevalence of hepatitis A virus IgG antibodies (anti-HAV), hepatitis B virus markers (anti-HBcAg and HBsAg) and hepatitis C virus antibodies (anti-HCV) in pregnant women. In HBsAg positive cases, HBeAg and hepatitis D virus antibodies (anti-HDV) were investigated. All analyses were performed with the ELISA technique. Results. Of the 1500 pregnant women studied, 93.3% were positive for anti-HAV IgG. The HBsAg seroprevalence was 0.26% and anti-HCV seroprevalence was 0.53%. There were no patients with HBeAg or antiHDV. Conclusions. A higher seroprevalence of HBsAg was found in this study than in other studies of pregnant Mexican women. We propose that HBsAg screening become a routine prenatal test.

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