New bacterial cellulose nanocomposites prepared by in situ radical polymerization of methacrylate monomers

Bacterial cellulose/polymethacrylate nanocomposites have received attention in numerous areas of study and in a variety of applications. The attractive properties of methacrylate polymers and bacterial cellulose, BC, allow the synthesis of new nanocomposites with distinct characteristics. In this study, BC/poly(glycidylmethacrylate) (BC/PGMA) and BC/poly(ethyleneglycol)methacrylate (BC/PPEGMA) nanocomposites were prepared through in situ free radical polymerization of GMA and PEGMA, respectively. Ammonium persulphate (APS) was used as an initiator and N,N’methylenebisacrilamide (MBA) was used as a crosslinker in BC/PGMA. Chemical composition, morphology, thermal stability, water absorption, mechanic and surface properties were determined through specific characterization techniques. The optimal polymerization was obtained at (1:2) for BC/PGMA, (1:2:0.2) ratio for BC/GMA/MBA and (1:20) for BC/PPEGMA, with 0.5% of initiator at 60 ºC during 6 h. A maximum of 67% and 87% of incorporation percentage was obtained, respectively, for the nanocomposites BC/PGMA/MBA and BC/PPEGMA. BC/PGMA nanocomposites exhibited an increase of roughness and compactation of the three-dimensional structure, an improvement in the thermal and mechanical properties, and a decrease in their swelling ability and crystallinity. On the other hand, BC/PPEGMA showed a decrease of stiffness of three-dimensional structure, improvement in thermal and mechanical properties, an increase in their swelling ability and a decrease the crystallinity. Both BC/polymethacrylate nanocomposites exhibited a basic surface character. The acid treatment showed to be a suitable strategy to modifiy BC/PGMA nanocomposites through epoxide ring-opening reaction mechanism. Nanocomposites became more compact, smooth and with more water retention ability. A decrease in the thermal and mechanical proprieties was observed. The new nanocomposites acquired properties useful to biomedical applications or/and removal of heavy metals due to the presence of functional groups.

Da crise do estado à democracia como alvo: Observações sobre o neoliberalismo a partir de Friedrich Hayek e Milton Friedman

The neoliberalism proclaims the crisis of the State in front of globalization , but, approaching two books taken as basic on this theoretical chain - The road to serfdom, of Friedrich Hayek, and Capitalism and Freedom, of Milton Friedman - to analyze this supposed dualism, the conclusion into which we arrive is another one. Remembering liberal tradition and quickly, later, analyzing critically the workmanships, can be perceived that others are the conflicts really gifts in the current capitalist reality - market versus State et capitalism versus democracy - and, from the understanding on the reading made and the theoretical trajectory of its authors, we may see as the neoliberalism locates itself in relation to these conflicts, which polar regions of these antagonisms privileges, what represents the State for itself, and what it intends as much more global philosophy than economic/politics thinking only

Gestão participativa em educação: compasso e descompasso de uma experiência de democracia no espaço escolar

This work aims at investigating the strategies of management used by State School Joaquim Jose de Medeiros, located in the city of Cruzeta - RN, as award practice of "School of Reference in Management", with a state title in 1999 at the beginning of the decade from 2000, being "Outstanding Brazil" from best management strategies nationally. In 2005, it is ranked among the best experiences of the state. It has been become complex by experiencing in that institution, but at the same time an enjoyable practice, mainly by using a social research, in a qualitative and quantitative approach, and a analysis of the institutional performance of two management practices: from 1995 to 2002 and from 2003 to 2007 . To understand the object, a investigative questionnaire was used with representatives of the school community and carried out an analysis of assessment of institutional and documents of institutional organization of the periods above in order to identify management strategies and examine the influences of the share capital, public policies , the institutional evaluation, in the process of democratic construction that has allowed achievements, highlighting Cruzeta, in the Seridó in the state of Rio Grande do Norte, semi-arid northeast, in the national and international juncture of well-successful experiences in management in institutional categories and leadership. This study becomes relevant to allow understand that the cultural practices of seridoenses that symbolize a capital generated by principles of trust, reciprocity, civic culture, as a driving force in overcoming the problems community and the conquest of democratic principles, worked for the school become a national reference in educational administration. Another aspect that made it natural that school was the collective creation of educational project with the participation and civic culture of self-evaluation as a way to understand the institutional practice and establish guidelines to improve the teaching and practice management in its many dimensions educational, social, administrative - financial and legal

As razões da esquerda radical PCB, PSTU e PSOL: estrutura organizativa e objetivos políticos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Direitos humanos e dilemas da democracia no Brasil: um estudo sociológico do trabalho policial (1985-2009)

According to the Public National Security Plan, the security is "[ ] a right by democratic excellence legitimately desired by all sectors of society, which is the fundamental right of citizenship, obligation of the constitutional state and responsibility of each one of us." The 1988 Constitution recognized the rights of life, liberty and personal integrity, considered torture and racial discrimination as crimes. The prime directive of the National Security and Citizenship (Law No. 11,707 of June 19, 2008 - PRONASCI-Brazil) expresses the commitment of the Brazilian state with the promotion of human rights. But despite this formal recognition, official violence continues to be used as a means of maintaining social order, consolidating a police action violating human rights (Amnesty International report "They go in shooting" - AI Index: AMR 19/025/2005) . This thesis analyzes the police work combined with the extension of citizenship rights, the spaces of freedom and democracy as a measure for the degree of affirmation or denial of the Human Rights in Brazil, and proposes the construction of a human friendly Police Force (Post - Colonial, Post-Abyss, Intercultural and Democratic)