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Novos complexos de Ru(II) e Mg(II) com flavonóides : atividade tóxica, sítios ativos e mecanismos de ação
(Universidade Federal de São Carlos, 2012-11-09) Oliveira, Regina Maria Mendes; Carlos, Rose Maria; https://lattes.cnpq.br/1589143355309943; https://lattes.cnpq.br/0972206150174877
The use of pesticides in agriculture, in order to enhance and ensure food production for a growing population has led to many concerns about risks to human health and the environment. Therefore, search for new strategies which seek a safer alternative is very important. With this aim, herein we describe new ruthenium(II) and magnesium(II) complexes containing phenanthroline and flavonoids (hesperidin, hesperetin, naringin or naringenin) ligand, These complexes were synthesized and characterized by elemental analysis (C,H,N), atomic absorption and ESI-MS(+). The structures were investigated by computational calculation and 1H, 13C NMR spectroscopic techniques. The complexes are stable in solid state, in most of the organic solvents tested and at various pH values. They are more hydrosoluble and liposoluble than the free flavonoides. The insecticidal activity bioassay against the leafcutting ants Atta sexdens rubropilosa demonstrated that the complexes show a delayed kill action. The activity of the Electrophorus electricus AChE enzyme was moderately inhibited by the Ru2+ complexes whereas the Mg2+ complexes were powerfull inhibitors only against AChE of Atta sexdens rubropilosa, indicating their high selectivity to insects. Further, the complexes are essentially non-toxic to the aquatic bacterium Vibrio fischeri and to human HeLa cells. The Mg2+ complexes presented unique properties: (i) in the electrochemical experiments in aqueous solution was observed the formation of a cyclic mechanism stable involving neutral, ionic and radical species; (ii) are better scavenger superoxide radical than the free flavonóides; (iii) presents a strong blue fluorescence. They act as an on/off fluorescent switch through the changing of the medium, solvents and pH. The fluorescence observed by confocal microscopy allowed to detect the high absorption of the magnesium complexes in the HeLa cells. Overall, the physicochemical and biological properties observed for Ru2+ and Mg2+ complexes opens new frontiers of application for these compounds in various areas of science such as agriculture, medicine, and optical materials.
Balanceamento da carga de um fluxo em múltiplos caminhos usando conceito de redes par-a-par
(Universidade Federal de São Carlos, 2012-11-09) Assumpção, Jorge Henrique de Barros; Marcondes, César Augusto Cavalheiro; https://lattes.cnpq.br/4431183539132719; https://lattes.cnpq.br/2249229617904124
The Internet suffer an increased amount of traffic. This increase could affect the structure of computer networks generating packet losses and delays. This loss and delay stems from the packet flows that generate more traffic that particular path or subpath, can support. Given this situation we show in this paper a mechanism based on P2P that balances the load by using multiple paths along with the breaking of the flow in smaller streams. For this mechanism called P2P-Flow that can be implemented in OpenFlow. In our simulation we compare this mechanism with multicast and unicast in multiple scenarios. The contributions of this work are detailed in the idea P2PFlow and compared with the multicast and unicast topology in various scenarios.
Oportunidades de aprendizagem organizacional na gestão de projetos: pesquisa-ação em uma empresa de engenharia consultiva
(Universidade Federal de São Carlos, 2012-11-09) Costa, Weslon Charles Ferreira; Toledo, José Carlos de; https://lattes.cnpq.br/9421627326330417; https://lattes.cnpq.br/1918314713540935
In recent years the possibility of incorporating the process of Learning Organizational (LO) during the life cycle of projects has been drawing the attention of scholars. However, there are few studies that analyze the subject in a practical and deeper way. The traditional studies try to consider and discuss the learning after the project more accurately due to its wide use in the business world. Nevertheless, the learning process may also occur during the projects when stimulated by mechanisms that systematize the externalization of knowledge and by means that encourage the sharing and the transference of them between projects team. Structured by means of a research action, this dissertation collaborate with the expansion of the knowledge about the subject investigating and improving actions that promote the practice of learning organizational during the development of projects in a medium-sized Consulting Engineering company from the civil construction sector located in the metropolitan region of São Paulo. The actions are guided aiming to promote the transference of explicit knowledge (technical documents and reports), the reuse of the learning from their own experiences and past history (tacit knowledge) and the systematic problem solving. The implemented actions were incorporated in the procedures of the Quality Management System of the Company and, from trainings, observations and informal and formal evaluations (internal and external audits) it was possible to point opportunities of improvements to reinforce the process of organizational learning during the development of projects. The research revealed that the transference of knowledge generated in documents, reports and technical studies to other projects is not effective in organizational level, being a lot more employed among the project coordinators with more length of service that know a larger number of projects performed or ongoing. In the other hand, despite the tacit experiences developed by the people (own experiences), the learning occurs when the coordinator of a project compulsorily identifies and registers in a Project Execution Plan (PEP) the similar developed or developing contracts in the company, interrelating them with the people involved in these contracts. Following the process, the plan is disclosed to the team members of this coordinator, which consult those people. The generation of knowledge provided by the dynamic of systematic problem solving appears as incipient because, in the consulting engineering, a lot of factors hinder the capture of this knowledge in the form of register for later reuse. Among these factors it is possible to mention: difficulty in determining the categories of problems that comprehend all the projects, imposition of the clients not to generate registers, hesitancy of the project coordinators to externalize the problems of the projects and, as a result, their reputations.