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Determinaçâo da toxicidade tópica e oral do inseticida fipronil e efeitos de suas doses subletais no comportamento de abelhas sem ferrão Melipona scutellaris (Latreille, 1811)
(Universidade Federal de São Carlos, 2012-05-09) Lourenço, Clara Tavares; Nocelli, Roberta Cornélio Ferreira; https://lattes.cnpq.br/8934724759636382; https://lattes.cnpq.br/4674980501476375
Melipona scutellaris bee, known as "uruçu" belong to the tribe Meliponini, popularly called stingless bees. This bee is endemic in northeastern Brazil and is distinguished by its ease of domestication and management, significant honey production and potential for pollination in greenhouses and open field. The insecticide fipronil acts on the insect nervous system by blocking the chloride channels through of the receptors gamma-aminobutyric acid (GABA) and glutamate (GluCl). Widely used in Brazil and more than 70 countries is considered highly toxic to bees, which is why its use was banned in France in 2004. Toxicological studies of pesticides to bees use mostly as a model species A. mellifera bee, which sublethal doses of fipronil can cause behavioral changes related to core tasks for the colony, such as feeding and foraging. However, differences in susceptibility between species of bees to insecticides may expose native bees there is a greater risk. The aim of this study was to determine the topical LD50 and oral LC50 of insecticide fipronil for stingless bee M. scutellaris and evaluate the effects of fipronil sublethal doses and concentrations in the locomotor activity and in the Proboscis Extension Reflex (PER) these bees. Foragers were collected in the output of three different colonies, consisting of three repetitions with ten bees each and they were placed in plastic pots of 250 mL. Bees subjected to topical treatments were anesthetized with CO2 and received 1.0 μL insecticide solution on pronotum with previously established doses (0.0, 0.5, 1.0, 1.5, 2.0, 2.5 and 5.0 ng of fipronil / μL solution), applied with a repetitive automatic micropipette. Bees subjected to oral contamination received sucrose solution contaminated with concentrations of fipronil determined previously (0.0, 0.005, 0.01, 0.03, 0.05, and 0.5 ng a.i./ μL sucrose solution) for 24 hours. The insecticide fipronil was considered highly toxic to these bees, both topically and orally. The topical intoxication resulted in a LD50 (48 hours) was 0.41 ng / bee (4.1 ng / g bee). The oral contamination resulted in a LC50 (48 hours) was 0.011 ng / μL of sucrose solution or, considering the amount of food they forage M. scutellaris consume daily in an oral LD50 of 0.6 ng a.i. / bee. The topic sublethal dose 0.05 ng a.i./bee and oral sublethal concentration 0.0011 ng a.i./ μL sucrose solution were cause significant changes for the locomotor activity these bees. The PER don't was a functional methodology for M. scutellaris bees. Results show that the bee M. scutellaris is more sensitive to fipronil than A. mellifera and that fipronil sublethal dose and concentrations affected the locomotor activity these bees.
Internet e campanhas eleitorais: experiências interativas nas cibercampanhas presidenciais do Cone Sul
(Universidade Federal de São Carlos, 2012-05-09) Iasulaitis, Sylvia; Azevedo, Fernando Antonio Farias de; https://lattes.cnpq.br/4226275371443693
In this thesis we develop an analysis aiming to understand the new formatting of politics in the era of Web 2.0. The overall objective was to investigate "if" and "how" the Internet's potential for human interaction was used by the candidates and coalitions in recent presidential campaigns in the Southern Cone and "if" and "how far" the interactive tools on websites electoral were used to strengthen ties with the electorate during political campaigns and increase the quality of democratic processes. In this thesis we seek to allow two levels of analysis: the formal structure of the website and political action that it develops. We analyze the logic of the candidates' campaign coordination in the use of discussion forums for government proposals, the constraints and incentives to encourage participation of ordinary citizens and the level of control exercised, and on the other hand, the way they interacted with Internet campaigns, with candidates and each other from these tools, the form and content of discursive exchanges held there and the nature of the proposals that resulted from this interaction. We start from the assumption that the availability of online discussion forums create an opportunity structure that can increase the possibility of political action of ordinary citizens to communicate their preferences, perform inputs, participate in the construction of political projects, as well as compel the candidates to conceive with more clearly their political platforms. However, the type of product is the result of the design of the interface and how the Internet and using the candidate technology, rather than a pre-determined by it, ie, depends on how the rules are articulated objective, strategies election, the political interest and the ability of the actors involved. We tested six corollaries specific empirical contexts and concrete objects of our investigation were the platforms for discussion and collaborative construction of government programs of four presidential candidates from Argentina, Chile and Brazil during the 2007 elections, 2009 and 2010, respectively, and the corpus of empiricalresearch in 2727 totaled posts analyzed. For purposes of this study, we performed a composition techniques that resulted in a specific methodological apparatus, including observation of interactions mediated by the computer, data collection and content analysis. The model consists of a first effort to develop a methodological research strategy discussion forums established in the electoral environment of websites. The evaluation of the quality of the discussions was undertaken according to eight dimensions of analysis based on methodological parameters DQI - Discourse Quality Index (Constraints and incentives for participation, inclusiveness and diversity, reciprocity debate, mutual respect, Identification, Degree of heterogeneity, thematization and effectiveness of content and interactive interface), which were operationalized into indicators, qualitative and quantitative.
Estudo da ruptura dielétrica durante a anodização de zircônio e o seu efeito sobre o processo de dopagem anódica de ZrO2
(Universidade Federal de São Carlos, 2012-05-09) Santos, Janaina Soares; Souza, Ernesto Chaves Pereira de; https://lattes.cnpq.br/1505400360366643; https://lattes.cnpq.br/5802009429183443
In this work the fundamental aspects of electrolytic breakdown in ZrO2 films were investigated. The electrolytic breakdown is a type of dielectric breakdown that occurs during galvanostatic growth of anodic oxides. To perform this investigation, the study was divided in two parts: (i) the modification of ZrO2 films by anodic doping and (ii) characterization of the electrical discharges (sparks) that appears on the electrode surface during zirconium anodization. The anodic doping study aimed to monitor the system and analyze the influence of current density, temperature and dopant concentration on the electrochemical, morphological and microstructural properties of ZrO2 films doped with calcium and niobium ions. The factorial design technique was used to optimize the number of experiments and quantify the effects of experimental variables on the responses. The results showed that all variables influenced the electrochemical response, leading to changes in morphology and microstructural properties of the ZrO2 doped films. This result was observed because these variables can affect the mobility of ionic species, ionic transport inside the oxide, the electrolyte resistivity and the dissolution process of the oxide. The spark characterization study aimed to investigate the evolution of electrical discharges during the experiment and correlate them with the processes observed in the anodization curve of zirconium. Hence, the electrode surface was recorded during the experiments using a high definition and high speed video camera. The image analysis allowed the calculation of the size, quantity and lifetime of the sparks discharges. Due to the enormous amount of data, it was necessary to develop a new methodology to analyzing the results. The methods used were based on techniques of imaging processing and multivariate data analysis. The use of these techniques coupled to electrochemical ones provided new insights that elucidated some aspects of the breakdown phenomenon. Furthermore, it provided guidelines for the implementation of future work.
O estágio na licenciatura em matemática : um espaço de formação compartilhada de professores
(Universidade Federal de São Carlos, 2012-05-09) Andrade, José Antônio Araújo; Passos, Cármen Lúcia Brancaglion; https://lattes.cnpq.br/8887795744073669
The main objective of this research was to analyze the potential of a work shared between current and future Mathematics teachers. The focus of this research is the learning of teaching, which is established by the relation with the knowledge, or in this case, with the knowledge mobilized in the context of pedagogic practices. The following problematic were formulated: which knowledge is mobilized and/or (trans)formed on learning of teaching in a context of shared work? Which elements act or make possible the learning of teaching and professional development in a context of shared work? The option was to investigate an experience of shared work through written or oral narratives. Data collection was done during the school year of 2009. Twenty one students of graduation, ten collaborator professors and the advisor/researcher took part in this research. Ten work teams were constituted, which compounded the investigation scenario. The following aspects were analyzed: the reflexive process of graduation students during their participation and learning while teaching Mathematics in the scholar context, the possibilities and potential of collaborative work for the teacher formation through the internship and for the consolidation of the teaching profession, the knowledge and reflection initiated in this process, and the contributions for the supervised internship for the continuing formation and for Scholar Mathematics ideas of these actors. The analysis of the content allowed us to establish four meaning units: professionalization; learning of teaching; tensions and contradictions, and cultural confrontations (relationship university school). It is necessary to consider that from this four meaning units, the first two were took as categories of analysis. In these units it was possible to note the formation potential on the constitution of multiple learning. An identity process was established between the trainees and the profession in the reflection moments about practices with which they started interacting. Diverse knowledge was mobilized, which culminated on the learning related to: curriculum management in Mathematics (classes planning and their conduction guided by an investigative and problematizing posture; the meaning of evaluative processes; the importance of interactions in classroom for the establishment of a learning environment for the students). Moreover, it was possible to identify important aspects of the professional development of the supervisor teacher, which characterize the beginning of her self-management in relation to her formation process. This research allowed us to glimpse a new course for internship activities in which the relationship between university and school is strengthened in order to look for possibilities or strategies that look for the better interaction among the subjects of these activities, thinking that the evolution of teaching professionalization depends on an initial formation that provides autonomy to the subject management of its own professional practices.