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The establishment of sulfate (SO42-) reduction during methanogenesis may considerably hinder the efficient energetic exploitation of methane, once removing sulfide from biogas is obligate and can be costly. In addition, sulfide generation can negatively impact the performance of methanogens by triggering substrate competition and sulfide inhibition. This study investigated the impacts of removing SO42- during fermentation on the performance of a second-stage methanogenic continuous reactor (R2), comparing the results with those obtained in a single-stage system (R1) fed with SO42--rich wastewater (SO42- of up to 400 mg L-1, COD/SO42- of 3.12-12.50). The organic load (OL) was progressively increased to 5.0 g COD d-1 in both reactors, showing completely discrepant performances. Sulfate-reducing bacteria outperformed methanogens in the consumption for organic matter during the start-up phase (OL = 2.5 g COD d-1) in R1, directing up to 73% of the electron flow to SO42- reduction. An efficient methanogenic activity was established in R1 only after decreasing the OL to 0.625 g COD d-1, after which methanogenesis prevailed by consuming ca. 90% of the removed COD. Nevertheless, high sulfide proportions (up to 3.1%) were measured in biogas. Conversely, methanogenesis was promptly established in R2, resulting in a methane-rich (> 80%) and sulfide-free biogas regardless of the operating condition. From an economic perspective, processing the biogas evolved from R2 would be cheaper, although the techno-economic impacts of managing the sulfur pollution in the fermentative reactor still need to be understood.

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The objective of this study was to assess the photolysis-mediated degradation of malathion in standard and commercial formulations, and to determine the toxicity of these degraded formulations. Degradation tests were carried out with 500 µg L-1 of malathion and repeated three times. The initial and residual toxicity was assessed by using Lactuca sativa seeds for phytotoxicity, Stegomyia aegypti larvae for acute toxicity, and Stegomyia aegypti mosquitoes (cultivated from the larval stage until emergence as mosquitoes) to evaluate the biochemical markers of sublethal concentrations. For the standard formulations the photolytic process efficiently reduced the initial concentration of malathion to levels below the regulatory limits however, the formation of byproducts was revealed by chromatography, which allowed for a more complete proposal of photolytic-mediated malathion degradation route. The degraded formulations inhibited the growth of L. sativa seeds, while only the untreated formulations showed larvicidal activity and mortality. Both formulations slightly inhibited acetylcholinesterase activity in S. aegypti mosquitoes, while the standard formulation decreased and the commercial formulation increased glutathione S-transferase activity. However, there were no significant differences for superoxide dismutase, esterase-α, esterase-ß and lipid peroxidation. These findings indicate that in the absence of the target compound, the presence of byproducts can alter the enzymatic activity. In general, photolysis effectively degrade malathion lower than the legislation values; however, longer treatment times must be evaluated for the commercial formulation.

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Due to the slow growth rate of anammox bacteria, enriched sludge is required for the rapid start-up of anammox-based reactors. However, it is still unclear if long-term stored anammox sludge (SAS) is an effective source of inoculum to accelerate reactor start-up. This study explored the reactivation of long-term SAS and developed an efficient protocol to reduce the start-up period of an anammox reactor. Although stored for 13 months, a low level of the specific anammox activity of 28 mg N/g VSS/d was still detected. Experimental Phase 1 involved the direct application of SAS to an upflow sludge bed reactor (USB) operated for 90 d under varying conditions of hydraulic retention time and nitrogen concentrations. In Phase 2, batch runs were executed prior to the continuous operation of the USB reactor. The biomass reactivation in the continuous flow reactor was unsuccessful. However, the SAS was effectively reactivated through a combination of batch runs and continuous flow feed. Within 75 days, the anammox process achieved a stable rate of nitrogen removal of 1.3 g N/L/day and a high nitrogen removal efficiency of 84.1 ± 0.2%. Anammox bacteria (Ca. Brocadia) abundance was 37.8% after reactivation. These overall results indicate that SAS is a feasible seed sludge for faster start-up of high-rate mainstream anammox reactors.

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A terapia de casal tradicionalmente restringiu seu interesse pela linguagem verbal, considerando pouco outras formas linguísticas. A fim de investigar alternativas terapêuticas, este estudo buscou compreender os processos relacionais de coconstrução de sentidos mediante a criação de desenhos na clínica de casal. Metodologicamente os dados foram coletados usando a vídeo-gravação de três casais em atendimento terapêutico. A análise dos dados, fundamentada na poética social, incluiu as transcrições de todas as sessões, seguidas de sua leitura, que possibilitou a identificação de diferentes usos do desenho, caracterizados como forma de: (a) promover a conversa inviabilizada pela tensão; (b) sinalizar o foco e a seleção da conversa; (c) explorar o ainda não-dito na conversa; (d) fortalecer descrições e narrativas na conversa e (e) sintetizar o processo avaliatório. A conclusão foi que o desenho consiste em uma nova linguagem que, incorporada à usual, permitirá a aprendizagem de novos gestos e a produção de novos sentidos.

Couple therapy has traditionally restricted its interest to verbal language, giving little consideration to other linguistic forms. In order to investigate alternative therapeutics, the present study sought to further understand the relational processes of co-construction of meaning through the creation of drawings, in the clinical setting. Methodologically, the data were collected using video recordings of three couples. Data analysis, grounded in social poetics, included the transcripts of all sessions, followed by readings of these transcripts that enabled identification of different uses of the drawings. These included: (a) promote discussion inviable because of tension; (b) signal the focus and selection of the discussion; (c) explore the as yet unsaid in the discussion; (d) strengthen descriptions and narratives of the conversation and (e) summarize the evaluative process. It was concluded that the drawing constitutes a new language, which when incorporated into the usual, allows for the learning of innovative attitudes and the production of new meanings.

Terapia de pareja tradicionalmente restringida su interés por los recursos del lenguaje verbal, dando muy poca consideración a otras formas lingüísticas. En un intento por investigar las alternativas terapéuticas, este estudio ha tratado de comprender los procesos relacionales de co-construcción de significado a través de la creación del dibujo en la clínica de la pareja. Metodológicamente la recolección de datos se llevó a cabo a través de grabaciones de video de tres tratamientos terapéuticos. El análisis de datos, basado en la poética sociales, incluido las transcripciones de todas las sesiones, seguidas por las lecturas que permitieron la identificación de los diferentes usos del dibujo, que se caracteriza por ser una forma de: (a) promover la conversación frustrada por la tensión; (b) señalar el enfoque y la selección de la conversación; (c) explorar la aún no dicho en la conversación; (d) fortalecer las descripciones y narraciones en la conversación y (e) sintetizar el proceso evaluativo. La conclusión fue que el dibujo consiste en un nuevo lenguaje, que cuando se incorporen a la habitual, permite el aprendizaje de nuevos gestos y la producción de nuevos significados.

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Este estudo tem como objetivo apresentar uma revisão das dissertações defendidas no Programa de Pós-Graduação em Psicologia da Universidade Federal de Uberlândia concernentes à Psicologia da Saúde. No total, 16 dissertações foram examinadas em função de um conjunto de dimensões de análise. Os resultados possibilitam a obtenção de um panorama acerca das dissertações em questão e o delineamento de novas perspectivas. Sugere-se, por exemplo, a opção por temáticas relativas à Psicologia da Saúde Pública em dissertações futuras, buscando-se contribuir para a formulação de propostas para a gestão de serviços ou para o aprimoramento de intervenções em diferentes níveis de atenção. E tal sugestão se estende aos pesquisadores brasileiros em geral, pois se revela potencialmente proveitosa para o avanço da Psicologia da Saúde no país, particularmente no sentido de promover uma maior articulação entre a produção do conhecimento científico e as demandas da realidade social no contexto nacional

This study aims to present a review of dissertations submitted to the Psychology Postgraduate Program at the Universidade Federal de Uberlândia concerning Health Psychology. In total, 16 dissertations were examined considering a set of analytical dimensions. The results can provide an overview about the Postgraduate Program production and the design of new perspectives. A suggestion is for the preference for new dissertations that focus on the theme of public health policies, hoping to contribute to new propositions for the different health care levels. This suggestion is valid for all Brazilian researchers, once it contributes to knowledge development in the area of health care in the country and, particularly, promotes a better articulation between scientific knowledge production and social needs

Assuntos

RESUMO

Este estudo tem como objetivo apresentar uma revisão das dissertações defendidas no Programa de Pós-Graduação em Psicologia da Universidade Federal de Uberlândia concernentes à Psicologia da Saúde. No total, 16 dissertações foram examinadas em função de um conjunto de dimensões de análise. Os resultados possibilitam a obtenção de um panorama acerca das dissertações em questão e o delineamento de novas perspectivas. Sugere-se, por exemplo, a opção por temáticas relativas à Psicologia da Saúde Pública em dissertações futuras, buscando-se contribuir para a formulação de propostas para a gestão de serviços ou para o aprimoramento de intervenções em diferentes níveis de atenção. E tal sugestão se estende aos pesquisadores brasileiros em geral, pois se revela potencialmente proveitosa para o avanço da Psicologia da Saúde no país, particularmente no sentido de promover uma maior articulação entre a produção do conhecimento científico e as demandas da realidade social no contexto nacional.(AU)

This study aims to present a review of dissertations submitted to the Psychology Postgraduate Program at the Universidade Federal de Uberlândia concerning Health Psychology. In total, 16 dissertations were examined considering a set of analytical dimensions. The results can provide an overview about the Postgraduate Program production and the design of new perspectives. A suggestion is for the preference for new dissertations that focus on the theme of public health policies, hoping to contribute to new propositions for the different health care levels. This suggestion is valid for all Brazilian researchers, once it contributes to knowledge development in the area of health care in the country and, particularly, promotes a better articulation between scientific knowledge production and social needs.(AU)

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RESUMO

Listeria monocytogenes, a foodborne pathogen causes listeriosis, a fatal disease in about 30% of cases that affects mainly immunocompromised persons. The aim of this research was to characterize L. monocytogenes pulsed-field gel electrophoresis (PFGE) types isolated from meat products collected at public markets in Araguaina city, TO. Sixty samples of raw ground beef and frescal sausage were analyzed during the second half of 2008. Five out of 30 samples (16.7%) of raw ground beef tested positive for L. monocytogenes, three of which were classified as serotype 1/2b and two as serotype 4b. Among the 30 samples of sausage collected, two strains of L. monocytogenes were isolated (6.7%), one of them belonging to serotype 1/2a and the other belonging to serotype 1/2b. The restriction enzymes used were ApaI and SmaI. Similarities among the strains were determined by Dice coefficient. The macro restriction profile obtained by using SmaI enzyme allowed the distribution of seven strains in two clusters, two pulsotypes and two subtypes. The result indicates that L. monocytogenes isolates, belonging to serotype 4b, 1/2a and 1/2b, are strongly correlated within the same serotype group, and in some cases among different serotypes, suggesting that they have a common source.

Listeria monocytogenes é um patógeno de origem alimentar que causa a listeriose, doença fatal em aproximadamente 30% dos casos, e que afeta principalmente pessoas imunocomprometidas. O presente trabalho teve como objetivo analisar os perfis PFGE de cepas de L. monocytogenes isoladas de produtos de origem animal, obtidos em mercados públicos da cidade de Araguaína, TO. Foram analisadas 60 amostras de carne moída crua e de linguiça frescal, no segundo semestre de 2008. Cinco (16,7%) das 30 amostras de carne moída crua foram positivas ao patógeno, sendo que três pertenciam ao sorotipo 1/2b e duas ao sorotipo 4b. Das 30 amostras de linguiça mista frescal, duas (6,7%) foram positivas para L. monocytogenes, sendo uma do sorotipo 1/2a e outra do 1/2b. Foram utilizadas as enzimas de restrição ApaI e SmaI. A similaridade entre eles foi determinada pelo coeficiente de Dice. A análise do perfil de macrorestrição com a enzima SmaI permitiu a distribuição dos sete isolados em dois clusters, dois pulsotipos e dois subtipos. Os resultados permitiram concluir que os isolados de L. monocytogenes sorotipos 4b, 1/2a e 1/2b foram fortemente correlacionados dentro dos mesmos sorotipos e em alguns casos entre diferentes sorotipos, sugerindo uma fonte comum.

RESUMO

Listeria monocytogenes, a foodborne pathogen causes listeriosis, a fatal disease in about 30% of cases that affects mainly immunocompromised persons. The aim of this research was to characterize L. monocytogenes pulsed-field gel electrophoresis (PFGE) types isolated from meat products collected at public markets in Araguaina city, TO. Sixty samples of raw ground beef and frescal sausage were analyzed during the second half of 2008. Five out of 30 samples (16.7%) of raw ground beef tested positive for L. monocytogenes, three of which were classified as serotype 1/2b and two as serotype 4b. Among the 30 samples of sausage collected, two strains of L. monocytogenes were isolated (6.7%), one of them belonging to serotype 1/2a and the other belonging to serotype 1/2b. The restriction enzymes used were ApaI and SmaI. Similarities among the strains were determined by Dice coefficient. The macro restriction profile obtained by using SmaI enzyme allowed the distribution of seven strains in two clusters, two pulsotypes and two subtypes. The result indicates that L. monocytogenes isolates, belonging to serotype 4b, 1/2a and 1/2b, are strongly correlated within the same serotype group, and in some cases among different serotypes, suggesting that they have a common source.

Listeria monocytogenes é um patógeno de origem alimentar que causa a listeriose, doença fatal em aproximadamente 30% dos casos, e que afeta principalmente pessoas imunocomprometidas. O presente trabalho teve como objetivo analisar os perfis PFGE de cepas de L. monocytogenes isoladas de produtos de origem animal, obtidos em mercados públicos da cidade de Araguaína, TO. Foram analisadas 60 amostras de carne moída crua e de linguiça frescal, no segundo semestre de 2008. Cinco (16,7%) das 30 amostras de carne moída crua foram positivas ao patógeno, sendo que três pertenciam ao sorotipo 1/2b e duas ao sorotipo 4b. Das 30 amostras de linguiça mista frescal, duas (6,7%) foram positivas para L. monocytogenes, sendo uma do sorotipo 1/2a e outra do 1/2b. Foram utilizadas as enzimas de restrição ApaI e SmaI. A similaridade entre eles foi determinada pelo coeficiente de Dice. A análise do perfil de macrorestrição com a enzima SmaI permitiu a distribuição dos sete isolados em dois clusters, dois pulsotipos e dois subtipos. Os resultados permitiram concluir que os isolados de L. monocytogenes sorotipos 4b, 1/2a e 1/2b foram fortemente correlacionados dentro dos mesmos sorotipos e em alguns casos entre diferentes sorotipos, sugerindo uma fonte comum.