360 resultados para Sauva (Formiga)


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Conselho Nacional de Desenvolvimento Científico e Tecnológico

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In this study, we investigated the role of routes and information attainment for the queenless ant species Dinoponera quadriceps foraging efficiency. Two queenless ant colonies were observed in an area of Atlantic secondary Forest at the FLONA-ICMBio of Nisia Floresta, in the state of Rio Grande do Norte, northeastern Brazil, at least once a week. In the first stage of the study, we observed the workers, from leaving until returning to the colony. In the second stage, we introduced a acrylic plate (100 x 30 x 0,8 cm) on a selected entrance of the nest early in the morning before the ants left the nest. All behavioral recordings were done through focal time and all occurence samplings. The recording windows were of 15 minutes with 1 minute interval, and 5 minute intervals between each observation window. Foraging was the main activity when the workers were outside the nest. There was a positive correlation between time outside the nest and distance travelled by the ants. These variables influenced the proportion of resource that was taken to the nest, that is, the bigger its proportion, the longer the time outside and distance travelled during the search. That proportion also influenced the time the worker remained in the nest before a new trip, the bigger the proportion of the item, the shorter was the time in the nest. During all the study, workers showed fidelity to the route and to the sectors in the home range, even when the screen was in the ant´s way, once they deviated and kept the route. The features of foraging concerning time, distance, route and flexibility to go astray by the workers indicate that decisions are made by each individual and are optimal in terms of a cost-benefit relation. The strategy chosen by queenless ants fits the central place foraging and marginal value theorem theories and demonstrate its flexibility to new informations. This indicates that the workers can learn new environmental landmarks to guide their routes

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The Quadratic Minimum Spanning Tree Problem (QMST) is a version of the Minimum Spanning Tree Problem in which, besides the traditional linear costs, there is a quadratic structure of costs. This quadratic structure models interaction effects between pairs of edges. Linear and quadratic costs are added up to constitute the total cost of the spanning tree, which must be minimized. When these interactions are restricted to adjacent edges, the problem is named Adjacent Only Quadratic Minimum Spanning Tree (AQMST). AQMST and QMST are NP-hard problems that model several problems of transport and distribution networks design. In general, AQMST arises as a more suitable model for real problems. Although, in literature, linear and quadratic costs are added, in real applications, they may be conflicting. In this case, it may be interesting to consider these costs separately. In this sense, Multiobjective Optimization provides a more realistic model for QMST and AQMST. A review of the state-of-the-art, so far, was not able to find papers regarding these problems under a biobjective point of view. Thus, the objective of this Thesis is the development of exact and heuristic algorithms for the Biobjective Adjacent Only Quadratic Spanning Tree Problem (bi-AQST). In order to do so, as theoretical foundation, other NP-hard problems directly related to bi-AQST are discussed: the QMST and AQMST problems. Bracktracking and branch-and-bound exact algorithms are proposed to the target problem of this investigation. The heuristic algorithms developed are: Pareto Local Search, Tabu Search with ejection chain, Transgenetic Algorithm, NSGA-II and a hybridization of the two last-mentioned proposals called NSTA. The proposed algorithms are compared to each other through performance analysis regarding computational experiments with instances adapted from the QMST literature. With regard to exact algorithms, the analysis considers, in particular, the execution time. In case of the heuristic algorithms, besides execution time, the quality of the generated approximation sets is evaluated. Quality indicators are used to assess such information. Appropriate statistical tools are used to measure the performance of exact and heuristic algorithms. Considering the set of instances adopted as well as the criteria of execution time and quality of the generated approximation set, the experiments showed that the Tabu Search with ejection chain approach obtained the best results and the transgenetic algorithm ranked second. The PLS algorithm obtained good quality solutions, but at a very high computational time compared to the other (meta)heuristics, getting the third place. NSTA and NSGA-II algorithms got the last positions

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This work seeks to propose and evaluate a change to the Ant Colony Optimization based on the results of experiments performed on the problem of Selective Ride Robot (PRS, a new problem, also proposed in this paper. Four metaheuristics are implemented, GRASP, VNS and two versions of Ant Colony Optimization, and their results are analyzed by running the algorithms over 32 instances created during this work. The metaheuristics also have their results compared to an exact approach. The results show that the algorithm implemented using the GRASP metaheuristic show good results. The version of the multicolony ant colony algorithm, proposed and evaluated in this work, shows the best results

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This study aimed to analyse the factors that can contribute to the support of residents in the process of management of environmental tourism projects. The importance of reflecting on the municipal planning, including the management of stakeholders, is justified by changes in economic and social values of local communities, the concern with their space and quality of life. Thus, the support of the dwellers to the management process of an attractive allows motivate and prioritize the opinion of this community, strengthening social groups and integrating them into projects and local actions. The study was described as descriptive, exploratory and quantitative. As the analysis model. They were used the research variables done by Nunkoo and Ramkissoon (2012), as a way to assess the support of local dwellers on the development of Revitalization project of Monumento Natural Vale dos Dinossauros, in the management of environmental tourist destination, in Sousa/PB. Results show the relationship among the dimensions, confidence in government agencies, benefits and costs occasioned by tourism development in the attractive as influencers support elements of the deweller. Thus, it is intended to corroborate to the inclusion of stakeholdersin the planning process in the development of tourism in this location in order to involve them in decision making about planning and management of tourism in the city, with a view to sustainable local development

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O presente trabalho tem como objetivo investigar as características de filmes de SnO2 depositados em substrato de vidro borosilicato por um processo de silk-screen modificado para obtenção de espessura fina compatível com a aplicação em células solares policristalinas de baixo custo. O filme de SnO2 é um dos mais apropriados para obtenção de vidro TCO (transparent conductive oxide) para uso em células solares devido a sua baixa resistividade elétrica e alta transmitância, sendo quimicamente inerte, mecanicamente duro e tem resistência a altas temperaturas, o que facilita então a calcinação das amostras entre 500º C a 550º C. Os filmes foram obtidos a partir de uma solução precursora básica, preparada pela dissolução de SnCl2.2H2O em Etanol (99,5 %). Foi realizado um planejamento fatorial 2(3-1) para analisar a influência dos parâmetros concentração da solução precursora (CETN), temperatura de calcinação (TC) e taxa de aquecimento (tX) na calcinação, sendo a concentração CETN o parâmetro que apresentou maior efeito sobre os parâmetros de respostas investigados: espessura do filme (ω), resistividade de superfície (ρ) e a transmitância relativa (θ). Foi possível obter com a metodologia utilizada, filmes com espessuras da ordem de 1 Nm com resistividade de superfície de 10 / e transmitância relativa entre 70 e 80 %.

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The search for sustainable solutions through an appropriate environmental administration of the available natural resources, that comes from encounter to the aspirations of preservation of the environment and of the human being, in way to diagnose and to solve the environmental and social problems with the smallest possible impact to the nature and the man, it is the great challenge, so much for that generation, as for the future generations. The study of the environmental problems of the water and the participation and the social actors' environmental understanding as a whole, interferes in the field of the thematic environmental international, contemplating the strategic need of an appropriate administration of that very natural one, through a program returned to the diagnosis of the problems and in the search of compatible maintainable solutions, in a social and environmental politics of planning and environmental education, centered above all in the citizen's voice , user of that system. The present thesis she seeks to study the problem of the maintainable administration of the water, focusing the participation and the citizen's environmental understanding in the use of that very natural one for urban residential activities, in what concerns the approach and analyses of variables that treat of the measurement of general knowledge and you adapt, sense of community of the access to the means of information and of the attitudes and environmental behaviors, besides the variables of partner-demographic characterization or personal identification of the interviewed ones of an exploratory research of the type " survey ", accomplished through a stratified aleatory sampling, being the strata each one of the 4 (four) Political-Administrative Areas of the Natal city, having happened the collection of the data in the period of february to april/2002. The methodology used in this work it constitutes in the application of questionnaires with scales of the type Likert to measure the echo-varied of the study, besides a partner-demographic scale for the characterization of the studied sample. For the analysis of the results, it was made an exploratory descriptive study initially, followed by the use of techniques statistical multivariate s, such as, factorial analysis through the application of main components, besides the accomplishment of studies of multiple lineal regression. To complement this study, the accomplishment of Tests of Independence was proceeded through the Qui-square of Pearson, in way to verify the dependence of the associations between the partner-demographic variables and the principal selected variables and presents in the resulting factors of the factorial analysis. The results appear for a low level of environmental knowledge, of access to the information and community's sense, besides the verification that the principal factors resultants send for the need of feeling emphasis in the programs and administration actions addressed for the environmental understanding, the behaviors and attitudes that approach the information and the environmental education, besides the reuse of the water

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This study describes brittle deformation and seismicity in the Castanhão Dam region, Ceará State, Brazil. This reservoir will include a hidroeletric power plant and will store about 6,7 billions m3 of water. Five main litostratigraphic unit were identified in the region: gneissic-migmatitic basement, metavolcanosedimentary sequence, granitoid plutons of Brasiliano age, Mesozoic basaltic dike swarm, and Cenozoic fluvial terraces of the Jaguaribe river. The region has experienced several faulting events that occurred at different crustal levels. Faults formed at depths less than about 12 km present left-lateral movement and are associated with epidote and quartz infillings. Faults formed at depths less than 7 km are mainly strike-slip present cataclastic rocks, fault breccia and gouge. Both fault groups form mainly NE-trendind lineaments and represent reactivation of ductile shear zones or new formed faults that cut across existing structures. Seismically-induced liquefaction fractures take place in Cenozoic terraces and indicate paleoearthquakes that may have reached at leat 6,8 MS. In short, this work indicate that the level of paleoseismicity is much greater than one observed in the instrumental record. Several faults are favourably oriented for reactivation and induced seismicity should be expected after the Castanhão Dam impoudment

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The goals of this study were to evaluate techniques for collection of peritoneal fluid from calves, establish reference ranges for fibrinogen in peritoneal fluid during the 1st month of life, and determine if abomasal puncture would alter peritoneal fluid or hematologic variables. Twenty-two healthy Holstein calves underwent 3 peritoneal fluid collections on day 1, day 15, and day 30 of age. Fibrinogen concentration in peritoneal fluid was 0.20 g/dL and 0.10 g/dL (P < .05) for day 1 and day 30, respectively, and 0.10 at day 15 (P > .05) for calves without abomasal puncture. Plasma fibrinogen concentration was 0.60 g/dL and 0.70 g/dL (P < .05) for days 15 and 30, respectively, in calves without abomasal puncture. There were no significant differences (P <= .05) in peritoneal fluid and peripheral blood total protein and fibrinogen concentrations, specific gravity, total and differential cell count, or erythrocyte counts between calves with or without abomasal puncture. We concluded that the reference ranges established for fibrinogen and total protein concentration are important for accurate evaluation of peritoneal fluid in calves for further comparison with similar-aged animals with gastrointestinal-tract or abdominal-cavity disease. Additionally, accidental abomasal puncture does not alter values of fibrinogen, total protein, and nucleated cell Count in peritoneal fluid and does not cause apparent clinical abnormalities.

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Objective-To establish reference intervals for cytologic and biochemical variables in peritoneal fluid, whole blood, and plasma in calves with congenital umbilical hernias (CUHs) before and after herniorrhaphy and to assess whether those variables in calves with CUHs were altered, compared with findings in clinically normal calves.Animals-20 Holstein calves with or without a CUH.Procedures-10 calves with CUHs underwent herniorrhaphy. Blood and peritoneal fluid samples from all 20 calves were collected for cytologic and biochemical analyses on days 0 (before surgery), 1, 3, 5, 7, and 15. Data from the 2 groups were compared.Results-Reference intervals for the variables of interest were established for each group, Before surgery, calves with CUHs had significantly greater plasma total protein concentration and creatine kinase (CK) and aspartate aminotransferase activities and peritoneal fluid specific gravity values, compared with values for calves without CUHs. At various time points after surgery, peritoneal fluid total protein concentration; fibrinogen concentration; nucleated cell, polymorphonuclear cell, and lymphocyte counts; specific gravity; and lactate dehydrogenase, aspartate aminotransferase, and CK activities in calves with CUHs were significantly different from values in calves without CUHs. Some plasma and blood variables leg, total protein concentration, neutrophil count, and CK activity were significantly different between the 2 groups.Conclusions and Clinical Relevance-Values of certain cytologic and biochemical variables in peritoneal fluid, blood, and plasma were different between calves with and without CUHs. Thus, determination of reference intervals for these variables is important for interpreting diagnostic test results in calves with CUHs. (Am J Vet Res 2009;70:423-432)

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Com o objetivo de determinar a dinâmica do proteinograma sangüíneo e da atividade enzimática da gamaglutamiltransferase sérica de vacas antes e após o parto, foram utilizadas 26 vacas do período pré-parto até 180 dias após o parto, todas da raça Holandesa. Os resultados permitiram concluir que as vacas, no momento do parto, apresentam menores concentrações séricas de proteína total, das frações albumina e betaglobulina, bem como de imunoglobulinas G e M, do que nos períodos ante e pós-parto, apresentando, a partir dos nove dias pós-parto, elevação gradativa desses constituintes até os 180 dias após o parto. Não houve diferença na atividade da enzima gamaglutamiltransferase nos momentos estudados.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)