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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Theoretical and Practical Aspects of Ant Colony Optimization

Blum, Christian 23 January 2004 (has links)
Combinatorial optimization problems are of high academical as well as practical importance. Many instances of relevant combinatorial optimization problems are, due to their dimensions, intractable for complete methods such as branch and bound. Therefore, approximate algorithms such as metaheuristics received much attention in the past 20 years. Examples of metaheuristics are simulated annealing, tabu search, and evolutionary computation. One of the most recent metaheuristics is ant colony optimization (ACO), which was developed by Prof. M. Dorigo (who is the supervisor of this thesis) and colleagues. This thesis deals with theoretical as well as practical aspects of ant colony optimization. * A survey of metaheuristics. Chapter 1 gives an extensive overview on the nowadays most important metaheuristics. This overview points out the importance of two important concepts in metaheuristics: intensification and diversification. * The hyper-cube framework. Chapter 2 introduces a new framework for implementing ACO algorithms. This framework brings two main benefits to ACO researchers. First, from the point of view of the theoretician: we prove that Ant System (the first ACO algorithm to be proposed in the literature) in the hyper-cube framework generates solutions whose expected quality monotonically increases with the number of algorithm iterations when applied to unconstrained problems. Second, from the point of view of the experimental researcher, we show through examples that the implementation of ACO algorithms in the hyper-cube framework increases their robustness and makes the handling of the pheromone values easier. * Deception. In the first part of Chapter 3 we formally define the notions of first and second order deception in ant colony optimization. Hereby, first order deception corresponds to deception as defined in the field of evolutionary computation and is therefore a bias introduced by the problem (instance) to be solved. Second order deception is an ACO-specific phenomenon. It describes the observation that the quality of the solutions generated by ACO algorithms may decrease over time in certain settings. In the second part of Chapter 3 we propose different ways of avoiding second order deception. * ACO for the KCT problem. In Chapter 4 we outline an ACO algorithm for the edge-weighted k-cardinality tree (KCT) problem. This algorithm is implemented in the hyper-cube framework and uses a pheromone model that was determined to be well-working in Chapter 3. Together with the evolutionary computation and the tabu search approaches that we develop in Chapter 4, this ACO algorithm belongs to the current state-of-the-art algorithms for the KCT problem. * ACO for the GSS problem. Chapter 5 describes a new ACO algorithm for the group shop scheduling (GSS) problem, which is a general shop scheduling problem that includes among others the well-known job shop scheduling (JSS) and the open shop scheduling (OSS) problems. This ACO algorithm, which is implemented in the hyper-cube framework and which uses a new pheromone model that was experimentally tested in Chapter 3, is currently the best ACO algorithm for the JSS as well as the OSS problem. In particular when applied to OSS problem instances, this algorithm obtains excellent results, improving the best known solution for several OSS benchmark instances. A final contribution of this thesis is the development of a general method for the solution of combinatorial optimization problems which we refer to as Beam-ACO. This method is a hybrid between ACO and a tree search technique known as beam search. We show that Beam-ACO is currently a state-of-the-art method for the application to the existing open shop scheduling (OSS) problem instances.
162

Reduced Complexity Detection Techniques for Multi-Antenna Communication Systems

Tasneem, Khawaja Tauseef January 2013 (has links)
In a multiuser system, several signals are transmitted simultaneously within the same frequency band. This can result in significant improvements both in spectral efficiency and system capacity. However, a detrimental effect of the shared transmissions (both in time and bandwidth), is that the signal received at the base station (BS) or access point (AP) suffers from cochannel interference (CCI) and inter-symbol interference (ISI). This situation presents challenges to receiver design. To combat the destructive nature of multipath fading, a receiver often employs multiple antennas to collect the faded superimposed versions of the transmitted signals. The multiple signals are combined and processed in such a way that the effects of CCI and ISI are minimized and the desired information is reliably recovered. The situation is even more challenging when the system is operating under overload, i.e. when there are fewer receive antennas than there are transmitted signals. Multiuser detection (MUD) is used to simultaneously estimate the information sent by the transmitters. To do this, the receiver exploits differences among the cochannel signals (through unique spatial signatures in this case). We consider a cochannel communication system where multiple transmitted signals arrive at a receiver (equipped with multiple receive antennas) after propagating through a Rayleigh fading channel. It is assumed that the receiver is operating in an overloaded scenario. For such systems, an optimum maximum a posterior probability (MAP) detector estimates the transmitted signal by maximizing the probability of correct decision. The MAP detector reduces to the maximum likelihood (ML) detector when all the transmitted signals are equiprobable. The computational complexity of both MAP and ML detectors increases exponentially with the number of transmitted signals and the channel memory. For large systems suffering severe CCI and ISI, this is clearly not a good choice for real-time implementation due to the associated computational expenses. The main factors that influence the complexity of MAP / ML detection are: (i) the number of transmitted signals (or equivalently the number of users sharing the system resources), (ii) modulation alphabet size, and (iii) length of the channel memory. On the other hand, linear detection approaches fail to offer acceptable performance while other nonlinear sub-optimum approaches incur high computational costs for reasonably improved system performance and exhibit an irreducible error-floor at medium to high signal to noise ratio (SNR) values. We develop receiver signal processing techniques for the frequency-flat fading channel (where all the multipaths of the transmitted signal arrive at the receiver within a symbol period). We develop an ant colony optimization (ACO) assisted soft iterative detection approach for binary phase-shift keying (BPSK) modulated signals which employs a simplified MAP criteria to extract the most probable signals from the search space. The structure of the receiver is such that it can continue operating under overloaded conditions. The technique achieves near maximum likelihood (ML) performance in critically loaded cases using much lower complexity. For the challenging case of overload it still offers performance close to ML at low to moderate SNR values. Second, an integrated framework comprising of ACO metaheuristic and a recursively defined ML search criteria is developed to handle multilevel modulations. The proposed receiver is capable of achieving near-ML performance for the considered system with significant savings in computational complexity. The receiver framework is independent of the system loading condition, and therefore it remains suitable for overloaded scenarios. Due to the branch and bound nature of the algorithm, an exact expression for the complexity cannot be determined. Instead, an upper bound on computational complexity is developed.
163

Ant colony optimization based simulation of 3d automatic hose/pipe routing

Thantulage, Gishantha I. F. January 2009 (has links)
This thesis focuses on applying one of the rapidly growing non-deterministic optimization algorithms, the ant colony algorithm, for simulating automatic hose/pipe routing with several conflicting objectives. Within the thesis, methods have been developed and applied to single objective hose routing, multi-objective hose routing and multi-hose routing. The use of simulation and optimization in engineering design has been widely applied in all fields of engineering as the computational capabilities of computers has increased and improved. As a result of this, the application of non-deterministic optimization techniques such as genetic algorithms, simulated annealing algorithms, ant colony algorithms, etc. has increased dramatically resulting in vast improvements in the design process. Initially, two versions of ant colony algorithms have been developed based on, respectively, a random network and a grid network for a single objective (minimizing the length of the hoses) and avoiding obstacles in the CAD model. While applying ant colony algorithms for the simulation of hose routing, two modifications have been proposed for reducing the size of the search space and avoiding the stagnation problem. Hose routing problems often consist of several conflicting or trade-off objectives. In classical approaches, in many cases, multiple objectives are aggregated into one single objective function and optimization is then treated as a single-objective optimization problem. In this thesis two versions of ant colony algorithms are presented for multihose routing with two conflicting objectives: minimizing the total length of the hoses and maximizing the total shared length (bundle length). In this case the two objectives are aggregated into a single objective. The current state-of-the-art approach for handling multi-objective design problems is to employ the concept of Pareto optimality. Within this thesis a new Pareto-based general purpose ant colony algorithm (PSACO) is proposed and applied to a multi-objective hose routing problem that consists of the following objectives: total length of the hoses between the start and the end locations, number of bends, and angles of bends. The proposed method is capable of handling any number of objectives and uses a single pheromone matrix for all the objectives. The domination concept is used for updating the pheromone matrix. Among the currently available multi-objective ant colony optimization (MOACO) algorithms, P-ACO generates very good solutions in the central part of the Pareto front and hence the proposed algorithm is compared with P-ACO. A new term is added to the random proportional rule of both of the algorithms (PSACO and P-ACO) to attract ants towards edges that make angles close to the pre-specified angles of bends. A refinement algorithm is also suggested for searching an acceptable solution after the completion of searching the entire search space. For all of the simulations, the STL format (tessellated format) for the obstacles is used in the algorithm instead of the original shapes of the obstacles. This STL format is passed to the C++ library RAPID for collision detection. As a result of using this format, the algorithms can handle freeform obstacles and the algorithms are not restricted to a particular software package.
164

Life and limb : prosthetic citizenship in Serbia

Milosavljevic, Kate Louise January 2013 (has links)
The term ‘prosthetic’ is used increasingly across the social sciences and has taken on a theoretical life as a result of debates springing from contemporary studies of science and technology, medical anthropology and citizenship. This research considers whether the usage of ‘prosthetic’ and ‘prosthesis’ has however, become all too distanced from a grounded understanding of these terms, and is now in many ways synonymous with the term ‘cyborg’, therefore obscuring the specific relationships that prostheses represent. It asks if these terms have become a ‘catchall’ of technological subjectivities, without any basis in lived experience. Through ethnographic research into the manufacture, marketing and usage of medical prostheses in a Serbian inpatient rehabilitation centre, as well as interviews with prosthesis manufacturers, salespeople, as well with various citizens young and old, I present a nuanced view of the way in which citizenship itself is enacted. Citizenship is also a process of augmenting the body, both explicitly, such as in the (re)construction of socially acceptable bodies who have the capacity to labour, and implicitly, such as in the process of acquiring passports and identity documents. This process of externalising, and of the distributing of elements of the self into objects and relationships outside of the biological body forms the basis of what I term prosthetic citizenship. In my search for a grounded and ethnographically informed understanding of prostheses, and of prosthetic citizenship, key themes emerge, such as hope, normality, morality and the relationship of technology to the bodies. I find that prostheses are always sites of entanglement and paradox, but that they are also equally full of promise, and that in understanding how, why and in what capacities they are used, they emerge as capable of bridging the divide between theoretically complex abstract relationships, and the pragmatic realities of daily life.
165

Visual homing in field crickets and desert ants : a comparative behavioural and modelling study

Mangan, Michael January 2011 (has links)
Visually guided navigation represents a long standing goal in robotics. Insights may be drawn from various insect species for which visual information has been shown sufficient for navigation in complex environments, however the generality of visual homing abilities across insect species remains unclear. Furthermore variousmodels have been proposed as strategies employed by navigating insects yet comparative studies across models and species are lacking. This work addresses these questions in two insect species not previously studied: the field cricket Gryllus bimaculatus for which almost no navigational data is available; and the European desert ant Cataglyphis velox, a relation of the African desert ant Cataglyphis bicolor which has become a model species for insect navigation studies. The ability of crickets to return to a hidden target using surrounding visual cues was tested using an analogue of the Morris water-maze, a standard paradigm for spatial memory testing in rodents. Crickets learned to re-locate the hidden target using the provided visual cues, with the best performance recorded when a natural image was provided as stimulus rather than clearly identifiable landmarks. The role of vision in navigation was also observed for desert ants within their natural habitat. Foraging ants formed individual, idiosyncratic, visually guided routes through their cluttered surroundings as has been reported in other ant species inhabiting similar environments. In the absence of other cues ants recalled their route even when displaced along their path indicating that ants recall previously visited places rather than a sequence of manoeuvres. Image databases were collected within the environments experienced by the insects using custompanoramic cameras that approximated the insect eye viewof the world. Six biologically plausible visual homing models were implemented and their performance assessed across experimental conditions. The models were first assessed on their ability to replicate the relative performance across the various visual surrounds in which crickets were tested. That is, best performance was sought with the natural scene, followed by blank walls and then the distinct landmarks. Only two models were able to reproduce the pattern of results observed in crickets: pixel-wise image difference with RunDown and the centre of mass average landmark vector. The efficacy of models was then assessed across locations in the ant habitat. A 3D world was generated from the captured images providing noise free and high spatial resolution images asmodel input. Best performancewas found for optic flow and image difference based models. However in many locations the centre of mass average landmark vector failed to provide reliable guidance. This work shows that two previously unstudied insect species can navigate using surrounding visual cues alone. Moreover six biologically plausible models of visual navigation were assessed in the same environments as the insects and only an image difference based model succeeded in all experimental conditions.
166

Officially Categorized Queers : Strategies, Risks and Unintentional Effects When Navigating the Swedish Asylum Apparatus

Mellquist, Joanna January 2016 (has links)
This thesis investigates the experiences and strategies of queer migrants seeking asylum in Sweden due to sexuality and/or gender identity. By conducting ethnographic fieldwork and biographical interviews within the RFSL Newcomers support network, the thesis analyses how queer migrants navigate the Swedish asylum apparatus. Building on recent research in queer migration studies, it explores how power relations related to class, gender and race affect queer migrants’ strategies. Applying Bruno Latour’s Actor-Network theory, the thesis furthermore analyses the queer migrants in an actor network together with RFSL Newcomers and the asylum apparatus as independent actors. This thesis additionally aims to contribute to the sociological debate on categorization and construction of identity using Ian Hacking’s concept of the looping effect. Lack of social capital, of not having the right networks, gendered possibilities of visibility and speaking about sexuality can establish obstacles for queer migrants in the credibility assessment and the success of the asylum claim. The asymmetric power relation forces queer migrants into conflicting strategies. Forced visibility and hyper hiding are strategies that are specifically produced in relation to the asylum apparatus creating gendered risk and precarious living conditions. This thesis concludes that queer migrants and the RFSL Newcomers network, in their asylum activism both challenge the asylum apparatus and Western narratives of LGBTQ identity. Nevertheless, RFSL and the queer migrants become complicit in the production of official essentialistic LGBTQ identities when navigating the asylum apparatus. By exploring the Swedish context of LGBTQ asylum and categorization of LGBTQ identity in the asylum process, this thesis contributes to the somewhat undertheorized field of queer migration in Swedish academia.
167

Solving cardinality constrained portfolio optimisation problem using genetic algorithms and ant colony optimisation

Li, Yibo January 2015 (has links)
In this thesis we consider solution approaches for the index tacking problem, in which we aim to reproduces the performance of a market index without purchasing all of the stocks that constitute the index. We solve the problem using three different solution approaches: Mixed Integer Programming (MIP), Genetic Algorithms (GAs), and Ant-colony Optimization (ACO) Algorithm by limiting the number of stocks that can be held. Each index is also assigned with different cardinalities to examine the change to the solution values. All of the solution approaches are tested by considering eight market indices. The smallest data set only consists of 31 stocks whereas the largest data set includes over 2000 stocks. The computational results from the MIP are used as the benchmark to measure the performance of the other solution approaches. The Computational results are presented for different solution approaches and conclusions are given. Finally, we implement post analysis and investigate the best tracking portfolios achieved from the three solution approaches. We summarise the findings of the investigation, and in turn, we further improve some of the algorithms. As the formulations of these problems are mixed-integer linear programs, we use the solver ‘Cplex’ to solve the problems. All of the programming is coded in AMPL.
168

Evolução do sistema reprodutivo de formigas da tribo Attini (Hymenoptera : myrmiciane) : análise das espermatecas /

Ortiz, Gabriela. January 2007 (has links)
Resumo: A espermateca dos insetos estoca os espermatozóides desde a cópula até a fecundação dos ovos, e consiste de uma bolsa que freqüentemente possui glândulas associadas. Considerações sobre a anatomia, histologia e ultra-estrutura de espermatecas tornam-se muito mais complexas quando são considerados os insetos sociais, que apresentam diferenças no tamanho e na forma entre rainhas e operárias, e ainda, entre as espécies. Apesar desta complexidade, os resultados morfológicos, histoquímicos e ultra-estruturais aqui obtidos mostraram as diferenças entre as espermatecas das espécies: Atta sexdens rubropilosa, Atta laevigata, Atta sexdens sexdens, Atta sexdens piriventris, Atta capiguara, Acromyrmex balzani, Acromyrmex landolti, Acromyrmex landolti balzani, Acromyrmex coronatus e Cyphomyrmex muelleri. As espécies Atta sexdens rubropilosa, Atta laevigata, Acromyrmex coronatus e Cyphomyrmex muelleri apresentaram apenas a glândula espermatecal (porção secretora externa à espermateca). Atta sexdens sexdens, Atta capiguara e Acromyrmex landolti balzani apresentaram tanto a glândula espermatecal como um epitélio secretor interno. Atta sexdens piriventris, Acromyrmex balzani e Acromyrmex landolti, no entanto, apresentaram apenas epitélio secretor interno, sugerindo que nestas espécies a espermateca seja mais independente na manutenção dos espermatozóides. As formigas cortadeiras vêm sendo cada vez mais estudadas do ponto de vista filogenético, tendo como principal marcador o DNA mitocondrial. Estabelecer a filogenia das formigas atines auxiliaria na resposta de algumas questões evolutivas sobre a relação destas com seus fungos. Realizou-se aqui a correlação das informações obtidas através das seqüências de DNA e do estudo morfológico das espermatecas de rainhas Atta sexdens rubropilosa, Atta laevigata, Atta sexdens sexdens, Atta sexdens piriventris... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The insects spermatheca stores the spermatozoa from the copulation until the egg fecundation, and consists of a sac frequently associated with glands. Considerations about anatomy, histology and ultrastructure of spermathecae become much more complex in social insects, because they have queens and workers with different sizes and shapes, as well as among the species. Besides this complexity, the morphological, histochemical and ultrastructural results show the differences between the spermathecae of the following species: Atta sexdens rubropilosa, Atta laevigata, Atta sexdens sexdens, Atta sexdens piriventris, Atta capiguara, Acromyrmex balzani, Acromyrmex landolti, Acromyrmex landolti balzani, Acromyrmex coronatus and Cyphomyrmex muelleri. The species Atta sexdens rubropilosa, Atta laevigata, Acromyrmex coronatus and Cyphomyrmex muelleri presented only the spermathecal gland (external secretory portion). Atta sexdens sexdens, Atta capiguara and Acromyrmex landolti balzani presented both the spermathecal gland and an internal secretory epithelium. Atta sexdens piriventris, Acromyrmex balzani and Acromyrmex landolti, however, presented only the internal secretory epithelium, suggesting that the spermatheca in these species is more independent in spermatozoa maintenance. The leaf-cutter ants are being studied more from a phylogenetic point of view, having as a principal marker mitochondrial DNA. The establishment of the phylogeny of the attines ants would help in the response of some evolutionary questions about their relation with their fungus. The present study correlated the information obtained from the DNA sequences and morphological studies of spermathecae of Atta sexdens rubropilosa, Atta laevigata, Atta sexdens sexdens, Atta sexdens piriventris, Atta capiguara, Acromyrmex balzani, Acromyrmex landolti, Cyphomyrmex muelleri, Apterostigma sp. and Mycocepurus goeldii queens... (Complete abstract click electronic access below) / Orientador: Maria Izabel Camargo Mathias / Coorientador: Mauricio Bacci Júnior / Banca: José Eduardo Serrão / Banca: Maria Santina de Castro Morini / Banca: Odair Correa Bueno / Banca: José Roberto Feitosa Silva / Doutor
169

Reproduction and immunity in ant queens: Reproduction et immunité chez les reines de fourmis

Cherasse, Sarah 01 March 2019 (has links) (PDF)
Ants and other social Hymenoptera (social bees and wasps) have a remarkable mating strategy. Social Hymenoptera live in societies where reproduction is monopolized by a fertile caste consisting of males and queens. On the other hand, the logistical tasks of the colony are carried out by a sterile female caste known as workers. Reproductive individuals mate during a single bout early in their life and will never engage in additional reproductive events later on. Males die soon after mating while queens store millions of sperm cells in a specialized organ, the spermatheca. Queens will use this sperm stock to fertilize eggs during the rest of their life that can last up to several decades. With a record of 28.5 years in the black garden ant, ant queens have the longest lifespan recorded to date among the social Hymenoptera. In my thesis, I addressed three aspects of ant queen reproduction. First, I tested the effect of mating on the expression of several genes involved namely in fecundity, longevity and immunity. I found that mating induces an up-regulation of the yolk precursor vitellogenin and of the antimicrobial peptide defensin. Second, I measured the intensity of different immune responses in male and queen genital organs in order to determine which immune pathways are activated to protect sperm. Antimicrobial peptide genes are expressed in the genital tract of both sexes and the queen spermatheca is capable of strongly inhibiting bacterial growth. The immune melanization response is, however, overall inactive in the organs tested probably because its unspecific mode of action and cytotoxic by-products are likely to damage sperm cells. Immunity thus seems to be closely regulated in organs that are in contact with sperm. Third, I determined if activation of the queen immune system had an impact on the survival of sperm stored in the spermatheca. There is no detectable effect in young newly mated queens whereas, in one year old queens, immune activation induces a significant reduction in sperm viability. Life stage thus seems to influence queen ability to preserve sperm viability in the event of an immune challenge. In addition, one year old queens have higher sperm viability than newly mated queens suggesting queens are able to displace dead sperm cells from their spermatheca. Finally, I relied on the well-established sequence of behaviors inherent to the early life of ant queens to try to uncover the largely unknown roles of inotocin, the insect ortholog of the vertebrate hormones oxytocin and vasopressin, in regulating insect behavior. I measured gene expression of the inotocin receptor and found that it is highly expressed during social and reproductive behaviors, which is consistent with previous results in vertebrates. Inotocin might thus also be involved in modulating these behaviors in insects, but further studies are needed to be able to fully understand this complex signaling system. Overall, I show that reproduction and immunity are closely linked in ant queens and that the latter provide promising models for investigating the roles of hormones in insects. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
170

Estudo do compartilhamento de ant?genos entre Angiostrongylus spp. e outros helmintos

Cognato, Bianca Barbieri 28 February 2013 (has links)
Made available in DSpace on 2015-04-14T13:09:38Z (GMT). No. of bitstreams: 1 448197.pdf: 1838361 bytes, checksum: 7924b0b15d7d6da94d6a3c9d188d1048 (MD5) Previous issue date: 2013-02-28 / Two species of parasites nematode of Angiostrongylidae family, genus Angiostrongylus intra-arterial localization are capable of human desease production: Angiostrongylus costaricensis and Angiostrongylus cantonensis. Both species are rodent s parasites and the human infection is considered incidental. On humans, A. cantonensis cause eosinophilic meningitis and A. costaricensis cause abdominal angiostrongiliase. Since there is no elimination of parasitic forms in human infection, diagnosis becomes difficult and molecular methods are necessary. After years of discovery of angiostrongil?ases, there are still many efforts in the study and development of a specific and sensitive diagnostic test capable of discriminating Angiostrongyliases of the other parasites. In this context, cross-reactivity becomes a problem in specificity of serologic tests. The main objective of this study was to analyze the sharing of antigens between Angiostrongylus spp. and parasites Strongyloides spp., Fasciola hepatica, Ascaris lumbricoides, Hymenolepis diminuta and Toxocara canis, and identify these molecules shared. To obtain antigens, some rats were captures and their feces analyzed by the method of Baerman addition to being seeded Agar Plates. Were obtained larvae of Strongyloides spp. and Angiostrongylus spp. In pulmonary arteries were found 11 female worms and 2 male worms of A. cantonensis, which led to the first report of the occurrence of this parasite in Rio Grande do Sul. In the small intestine was obtained a Strongyloides spp worm and analysis of small intestine were obtained Hymenolepis diminuta worms. From the adult worms of parasites were obtained antigens used in this study. Furthermore, we used antigens of allergens such as peanut, tomato, strawberry and pollen. To identify shared antigens, proteins were separated by one and two dimensional electrophoresis technique assayed by Western blot using sera of patients with angiostrongyliases. All antigens were recognized by sera from patients infected with angiostrongyliases, being a total of fourteen bands identified as being immunogenic. The fourteen bands were cut out of polyacrylamide gels and analyzed by mass spectrometry. The proteins identified were: Phosphoenolpyruvate carboxykinase, heat shock protein 70 (HSP70), DAPPUDRAFT hypothetical protein, 60 kDa Chaperonin 5, Glyceraldehyde-3-phosphate dehydrogenase, sigma class GST Chain A, Glucose-6-phosphate isomerase, pyruvate dehydrogenase subunit E1, Glutamate dehydrogenase 2, arachin Ahy-1, Full = Allergen Ara h 1, clone P41B, Gly1. The data generated in this study show that there is sharing of antigens between organisms of different taxonomic groups, but also with allergens tested. Moreover, the description and analysis of shared molecular components can help in understanding the evolutionary history and phylogeny of these organisms. / Duas esp?cies de parasitos nemat?deos da fam?lia Angiostrongylidae, do g?nero Angiostrongylus de localiza??o intra-arterial s?o capazes de produzir doen?a em humanos: Angiostrongylus costaricensis e Angiostrongylus cantonensis. Ambas as esp?cies s?o parasitos pr?prios de roedores e a infec??o humana ? considerada acidental. No homem, A. cantonensis ? o causador da meningite eosinof?lica e A. costaricensis causador da angiostrongil?ase abdominal. Como n?o h? elimina??o de formas parasit?rias na infec??o humana, o diagn?stico se torna dif?cil e m?todos moleculares se tornam necess?rios. Depois de anos da descoberta das angiostrongil?ases, ainda h? muitos esfor?os no estudo e desenvolvimento de um teste de diagn?stico espec?fico e sens?vel capaz de discriminar as Angiostrongil?ases de outras parasitoses. Neste contexto, a reatividade cruzada se torna um problema na especificidade de testes sorol?gicos. O objetivo principal deste trabalho foi analisar o compartilhamento de ant?genos entre Angiostrongylus spp. e os parasitos Strongyloides spp., Fasciola hepatica, Ascaris lumbricoides, Hymenolepis diminuta e Toxocara canis, assim como identificar essas mol?culas compartilhadas. Para obten??o de ant?genos, algumas ratazanas foram capturas e suas fezes analisadas atrav?s do m?todo de Baerman al?m de terem sido semeadas em Placas de ?gar. Foram obtidas larvas de Strongyloides spp. e Angiostrongylus spp. Nas art?rias pulmonares de uma ratazana foram encontrados 11 vermes f?meas e 2 vermes machos de A. cantonensis, que deu origem ao primeiro relato da ocorr?ncia deste parasito no Rio Grande do Sul. No intestino delgado foi obtido um verme de Strongyloides spp e da an?lise do intestino delgado foram obtidos vermes de Hymenolepis diminuta. A partir dos vermes adultos dos parasitos, foram obtidos os ant?genos utilizados neste trabalho. Al?m disso, foram utilizados ant?genos de alergenos como o amendoim, tomate, p?len e morango. Para identifica??o dos ant?genos compartilhados, as prote?nas foram separadas por eletroforese uni e bidimensional ensaiadas pela t?cnica de Western-Blot utilizando-se soro de pacientes com angiostrongil?ases. Todos os ant?genos foram reconhecidos pelo soro de pacientes infectados com angiostrongil?ases, sendo um total de quatorze bandas identificadas como imunog?nicas. As quartorze bandas foram recortadas dos g?is de poliacrilamida e analisadas por espectrometria de massas. As prote?nas identificadas foram: Fosfoenolpiruvato carboxiquinase, Prote?na de choque t?rmico 70 (HSP70), Prote?na hipot?tica DAPPUDRAFT, 60 kDa Chaperonina 5, Gliceralde?do-3-fosfato-desidrogenase, Cadeia A sigma classe GST, Glucose-6-fosfato isomerase, Piruvato desidrogenase subunidade E1, Glutamato desidrogenase 2 , arachin Ahy-1, Full=Allergen Ara h 1, clone P41B , Gly1. Os dados gerados no presente trabalho demonstram que h? compartilhamento de ant?genos entre organismos de diferentes grupos taxon?micos, como tamb?m com os alergenos testados. Al?m disso, a descri??o e a an?lise de componentes moleculares compartilhados podem ajudar na compreens?o da hist?ria evolutiva e da filogenia destes organismos.

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