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In this study, sugarcane bagasse ash (SCBA), obtained as residue from the sugar mill, was used as an adsorbent for Acid Red 27 (AR27) removal from aqueous solutions. The ash characterization data showed 23.63% of organic compounds and silica (α-SiO2) as the most expressive inorganic compound (confirmed by X-ray diffractogram), the BET surface area had a value of 62.79 m2.g-1 and the pHpzc was 8.45. Regarding the adsorptive tests, the optimal initial pH to the dye removal was 2.0. The adsorption equilibrium reached in about 4 h contact time and optimum SCBA dosage was found to be 4 g.L-1. The pseudo-second order model best represented the adsorption kinetics. The Freundlich equation presented the best fit to the equilibrium data for the removal of AR27 by ash, with maximum adsorption capacity of 15 mg.g-1 at pH 2.0. Thermodynamic study indicate that AR27 adsorption on SCBA occurs through a physisorption mechanism, with ΔHºads < 15 kJ.mol-1. The ΔHºads evaluated by Vant' Hoff equation was explained as a combination of water desorption enthalpy, ΔHºW and isosteric like enthalpy, ΔHºD for the dye adsorption in liquid environment. The ΔHºD = 9.2 kJ.mol-1 was calculated from Clausius-Clapeyron approach. The effects of coexisting anions on the adsorption and regeneration and reuse of the adsorbent were also investigated. This study suggests that SCBA, which was used without any pretreatment, has the potential to be applied as a low-cost adsorbent to mitigate effluents contamination with AR27 dye at low concentrations.

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Resumo: O artigo busca contribuir com as discussões sobre a relação universidade e sociedade, abordando a inserção social dos programas de pós-graduação stricto sensu na área de Serviço Social. Apresenta breve histórico sobre a inserção social como critério de avaliação pela Capes, além de panorama da inserção social como subsídio para a produção de conhecimento e como dimensão que reflete o compromisso ético, político, profissional e social, com problemas da sociedade em nível local, regional e nacional.

Abstract: The article seeks to contribute to the discussions on the relationship between university and society, addressing the social insertion of stricto sensu graduate programs in the area of Social Work. It presents a brief history of social insertion as a criterion for evaluation by Capes, in addition to a panorama of social insertion as a subsidy for the production of knowledge and as a dimension that reflects the ethical, political, professional and social commitment to society's problems at the local level, regional and national.

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Este artigo, baseado em levantamento bibliográfico e documental, analisa a forma como a educação se insere no processo de luta de classes no contexto atual de degradação dos direitos sociais, resultante da efetivação de políticas neoliberais. Analisa as contradições entre distintos projetos de educação, ligadas ao processo de privatização dos serviços educacionais e descaracterização de seu sentido público e social. Contrariamente a essa tendência, discute-se uma concepção de educação capaz de articular-se a um projeto de superação do capitalismo, como condição para a emancipação humana. Aponta a atualidade do projeto ético-político do Serviço Social na construção de um projeto classista de educação que, ancorado na tradição marxista, valorize a formação profissional, a produção do conhecimento, o exercício profissional em articulação às lutas sociais em geral e em defesa da educação pública, laica, gratuita e de qualidade, referenciada em um projeto anticapitalista de sociedade.

This article, based on a bibliographical and documentary study, analyzes the way in which education is inserted in the process of class struggle in the current context of degradation of social rights, resulting from the implementation of neoliberal policies. It analyzes the contradictions between different education projects, related to the process of privatization of educational services and de-characterization of its public and social character. Contrary to this tendency, we discuss a conception of education capable of articulating with a project of overcoming capitalism as a condition for human emancipation. It points out the importance of the ethical-political project of the Social Service in the construction of a class-based education project that, anchored in the Marxist tradition, values professional qualification, knowledge production, and professional practice articulated to social struggles in general and in defense of public education, secular, free and of good quality, based on an anti-capitalist society project.

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Este artigo apresenta uma discussão sobre os conceitos fundamentais e o contexto de emergência histórica da teoria social marxiana, no período de constituição da sociedade moderna. Como contraponto, discute-se a constituição e o caráter das "ciências sociais", particularmente da sua vertente positivista, que, por um processo de segmentação da análise da sociedade, acaba por se afastar das possibilidades de apreensão, para além do nível fenomênico, da essência dos processos sociais, na perspectiva de uma totalidade articulada e historicamente constituída. O estudo, baseado em pesquisa bibliográfica, ratifica que o método marxiano articula-se profundamente a um projeto de transformação revolucionária da sociedade, que não prescinde do conhecimento cientificamente fundado da vida social.

This article presents a discussion on the fundamental concepts and the context of historical emergence of Marxian social theory, in the inception of modern society. As a counterpoint, discuss the constitution and character of the "social sciences", particularly the positivist aspect, which in a process of segmentation of analysis of society ends up moving away from possibilities of apprehending, beyond the phenomenal level, the essence of social processes from the perspective of an articulated and historically constituted totality. The study, based on a bibliographic research, ratifies that the Marxian method is deeply linked to a revolutionary transformation project of the society, which cannot be done without the knowledge scientifically founded on social life.

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Mist netting is a widely used technique to sample bird and bat assemblages. However, captures often decline with time because animals learn and avoid the locations of nets. This avoidance or net shyness can substantially decrease sampling efficiency. We quantified the day-to-day decline in captures of Amazonian birds and bats with mist nets set at the same location for four consecutive days. We also evaluated how net avoidance influences the efficiency of surveys under different logistic scenarios using re-sampling techniques. Net avoidance caused substantial declines in bird and bat captures, although more accentuated in the latter. Most of the decline occurred between the first and second days of netting: 28% in birds and 47% in bats. Captures of commoner species were more affected. The numbers of species detected also declined. Moving nets daily to minimize the avoidance effect increased captures by 30% in birds and 70% in bats. However, moving the location of nets may cause a reduction in netting time and captures. When moving the nets caused the loss of one netting day it was no longer advantageous to move the nets frequently. In bird surveys that could even decrease the number of individuals captured and species detected. Net avoidance can greatly affect sampling efficiency but adjustments in survey design can minimize this. Whenever nets can be moved without losing netting time and the objective is to capture many individuals, they should be moved daily. If the main objective is to survey species present then nets should still be moved for bats, but not for birds. However, if relocating nets causes a significant loss of netting time, moving them to reduce effects of shyness will not improve sampling efficiency in either group. Overall, our findings can improve the design of mist netting sampling strategies in other tropical areas.

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1. River system dynamics results in ecological heterogeneities that play a central role in maintaining biodiversity in riverine regions. In central Amazonia, large expanses of forest are seasonally flooded by nutrient-rich water (várzea forests) or by nutrient-poor water (igapó forests). Inundation patterns and the nutrient load of floodwaters are perhaps the most important abiotic factors determining spatial ecological variations in lowland Amazonia, and so they are expected to strongly influence the structuring of animal communities. 2. We examined how inundation patterns and water-nutrient load influence the structure of neotropical assemblages of bats, one of the most diverse vertebrate groups in tropical forests. Bat assemblages were sampled with mist nets in central Brazilian Amazonia, across a mosaic of várzea, igapó, and non-flooding nutrient-poor terra firme forests in the low- and high-water seasons. 3. An ordination analysis clearly separated the assemblages of the three forest types, demonstrating the structural relevance of both flooding and floodwater-nutrient load. Flooded forests had lower species richness because of the absence or rarity of species that make roosts out of leaves of understorey plants, and of those that feed on fruits of shrubs. Gleaning insectivores, also partly dependent on the understorey, were less abundant in flooded forests, but aerial insectivores more abundant, presumably because they benefited from a less cluttered foraging environment. These differences suggest that flooding affects bat assemblages mostly because it reduces the availability of niches associated with understorey vegetation, which tends to be sparser in flooded forests. 4. Nutrient-rich várzea forests had a bat biomass twice that of nutrient-poor igapó and unflooded forests. This difference was not only mostly due to a greater overall abundance of bats, but also attributable to a disproportionate higher abundance of large-bodied bat species. 5. We concluded that both flooding and floodwater-nutrient load are very important in the structuring of lowland Amazonian bat assemblages, with inundation mostly constraining the species composition of the assemblages, and water-nutrient load mostly influencing the abundance of species. The distinctiveness of bat assemblages associated with flooding emphasizes the need to preserve inundated forests, which are under particular pressure in Amazonia.

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