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Item A note on fundamental group of a one point-extension(2005-05) Assem, Ibrahim; Bustamante, Juan Carlos; Castonguay, Diane; Novoa, CristianMostrar mais In this note, we consider an algebra A which is a one-point extension of another algebra B and we study the morphism of fundamental groups induced by the inclusion of (the bound quiver of ) B into (that of ) A. Our main result says that the cokernel of this morphism is a free group and we prove some consequences from this fact.Mostrar mais Item Derived-tame blowing-up of tree algebras(2005-07) Castonguay, DianeMostrar mais Let k be an algebraically closed field and A be a tree algebra. We consider here a class obtained by the blowing-up of a tree algebra A at a set of vertices D of A, such an algebra is denoted by . The objective of this paper is to prove the equivalence between the derived-tameness and the non-negativity of the Euler form for algebras of this form. We also show that, in this case, if D is a non-empty set then must be derived equivalent to a special incidence algebra, called semichain algebra.Mostrar mais Item Strongly simply connected schurian algebras and multiplicative bases(2005-01) Assem, Ibrahim; Castonguay, Diane; Marcos, Eduardo do Nascimento; Trepode, Sonia ElisabetMostrar mais In this paper, we define concepts of crowns and quasi-crowns, valid in an arbitrary schurian algebra, and which generalise the corresponding concepts in an incidence algebra. We show first that a triangular schurian algebra is strongly simply connected if and only if it is simply connected and contains no quasi-crown. We then prove that the absence of quasi-crowns in a triangular schurian algebra implies the existence of a multiplicative basis.Mostrar mais Item On the diameter of the Cayley Graph Hl,p(2015) Castonguay, Diane; Ribeiro, André da Cunha; Kowada, Luis Antonio Brasil; Figueiredo, Celina Miraglia Herrera deMostrar mais The family H`;p has been de ned in the context of edge parti- tions. Subsequently, it was shown to be composed of Hamiltonian Cayley graphs, and that it is possible to determine the diameter of H`;p in O(`) time. The established properties such as the low di- ameter suggest the H`;p graph as a good topology for the design of interconnection networks. The p`1 vertices of the graph H`;p are the `-tuples with values between 0 and p 1, such that the sum of the ` values is a multiple of p, and there is an edge between two ver- tices if the two corresponding tuples have two pairs of entries whose values di er by one unit. Our goal is to nd the diameter of Cayley graph H`;p in time O(log(`+p)). In this work, we did this for some families of graphs. We also show that the diameter of H`;p is the same of Hp;`. Finally, we nd a tight upper bound on the diameter of H`;p.Mostrar mais Item Polynomial enumeration of chordless cycles on cyclically orientable graphs(2015) Castonguay, Diane; Dias, Elisângela SilvaMostrar mais In a nite undirected simple graph, a chordless cycle is an induced subgraph which is a cycle. A graph is called cyclically orientable if it admits an orientation in which every chordless cycle is cyclically oriented. We propose an algorithm to enumerate all chordless cycles of such a graph. Compared to other similar algorithms, the proposed algorithm has the advantage of nding each chordless cycle only once in time complexity O(n2), where n is the number of vertices.Mostrar mais Item A GPU-based implementation of the firefly algorithm for variable selection in multivariate calibration problems(2014-12) Paula, Lauro Cássio Martins de; Soares, Anderson da Silva; Lima, Telma Woerle de; Delbem, Alexandre Cláudio Botazzo; Coelho, Clarimar José; Galvão Filho, Arlindo RodriguesMostrar mais Several variable selection algorithms in multivariate calibration can be accelerated using Graphics Processing Units (GPU). Among these algorithms, the Firefly Algorithm (FA) is a recent proposed metaheuristic that may be used for variable selection. This paper presents a GPU-based FA (FA-MLR) with multiobjective formulation for variable selection in multivariate calibration problems and compares it with some traditional sequential algorithms in the literature. The advantage of the proposed implementation is demonstrated in an example involving a relatively large number of variables. The results showed that the FA-MLR, in comparison with the traditional algorithms is a more suitable choice and a relevant contribution for the variable selection problem. Additionally, the results also demonstrated that the FAMLR performed in a GPU can be five times faster than its sequential implementation.Mostrar mais Item Transcriptional profile of Paracoccidioides induced by oenothein B, a potential antifungal agent from the Brazilian Cerrado plant Eugenia uniflora(2013) Carvalho, Patrícia Fernanda Zambuzzi; Tomazett, Patrícia Kott; Santos, Suzana Costa; Ferri, Pedro Henrique; Borges, Clayton Luiz; Martins, Wellington Santos; Soares, Célia Maria de Almeida; Pereira, MaristelaMostrar mais Background: The compound oenothein B (OenB), which is isolated from the leaves of Eugenia uniflora, a Brazilian Cerrado plant, interferes with Paracoccidioides yeast cell morphology and inhibits 1,3-β-D-glucan synthase (PbFKS1) transcript accumulation, which is involved in cell wall synthesis. In this work we examined the gene expression changes in Paracoccidioides yeast cells following OenB treatment in order to investigate the adaptive cellular responses to drug stress. Results: We constructed differential gene expression libraries using Representational Difference Analysis (RDA) of Paracoccidioides yeast cells treated with OenB for 90 and 180 min. Treatment for 90 min resulted in the identification of 463 up-regulated expressed sequences tags (ESTs) and 104 down-regulated ESTs. For the 180 min treatment 301 up-regulated ESTs and 143 down-regulated were identified. Genes involved in the cell wall biosynthesis, such as GLN1, KRE6 and FKS1, were found to be regulated by OenB. Infection experiments in macrophages corroborated the in vitro results. Fluorescence microscopy showed increased levels of chitin in cells treated with OenB. The carbohydrate polymer content of the cell wall of the fungus was also evaluated, and the results corroborated with the transcriptional data. Several other genes, such as those involved in a variety of important cellular processes (i.e., membrane maintenance, stress and virulence) were found to be up-regulated in response to OenB treatment. Conclusions: The exposure of Paracoccidioides to OenB resulted in a complex altered gene expression profile. Some of the changes may represent specific adaptive responses to this compound in this important pathogenic fungus.Mostrar mais Item Transcriptional profile of Paracoccidioides spp. in response to itraconazole(2014) Silva Neto, Benedito Rodrigues da; Carvalho, Patrícia Fernanda Zambuzzi; Bailão, Alexandre Melo; Martins, Wellington Santos; Soares, Célia Maria de Almeida; Pereira, MaristelaMostrar mais Background: Itraconazole is currently used to treat paracoccidioidomycosis. The mechanism of action of azoles has been elucidated in some fungi, although little is known regarding its mechanism of action in Paracoccidioides spp. The present work focused on identification of regulated transcripts using representational difference analysis of Paracoccidioides spp. yeast cells treated with itraconazole for 1 and 2 h. Results: Paracoccidioides Pb01 genes up-regulated by itraconazole included genes involved in cellular transport, metabolism/energy, transcription, cell rescue, defense and virulence. ERG11, ERG6, ERG3, ERG5 and ERG25 were up-regulated at multiple time points. In vivo infection experiments in mice corroborated the in vitro results. Ergosterol levels and distribution were evaluated in Paracoccidioides Pb18 yeast cells, and the results demonstrate that both factors were changed in the fungus treated with itraconazole. Conclusion: To our knowledge, this is the first transcriptional analysis of Paracoccidioides spp. exposed to a triazole drug. Here acetyl seems to be intensively produced from different metabolic pathways to produce ergosterol by the action of ergosterol synthesis related enzymes, which were also affected in other fungi. Among the genes affected, we identified genes in common with other fungi, as well as genes unique to Paracoccidioides Pb01. Those genes could be considered target to new drugs. Voltage-gated Ca2+ alpha subunit (CAV), Tetracycline resistance protein (TETA) and Hemolisyn-iii channel protein (HLYiii) were found only here and a probably involvement with resistence to itraconazole could be investigated in the future. However our findings do not permit inference to current clinical practice.Mostrar mais Item The characterization of a new set of EST-derived simple sequence repeat (SSR) markers as a resource for the genetic analysis of Phaseolus vulgaris(2011) Garcia, Robertha Augusta Vasconcelos; Rangel, Priscila Nascimento; Brondani, Claudio; Martins, Wellington Santos; Melo, Leonardo Cunha; Carneiro, Monalisa Sampaio; Borba, Tereza Cristina Oliveira; Brondani, Rosana Pereira VianeloMostrar mais Background: Over recent years, a growing effort has been made to develop microsatellite markers for the genomic analysis of the common bean (Phaseolus vulgaris) to broaden the knowledge of the molecular genetic basis of this species. The availability of large sets of expressed sequence tags (ESTs) in public databases has given rise to an expedient approach for the identification of SSRs (Simple Sequence Repeats), specifically EST-derived SSRs. In the present work, a battery of new microsatellite markers was obtained from a search of the Phaseolus vulgaris EST database. The diversity, degree of transferability and polymorphism of these markers were tested. Results: From 9,583 valid ESTs, 4,764 had microsatellite motifs, from which 377 were used to design primers, and 302 (80.11%) showed good amplification quality. To analyze transferability, a group of 167 SSRs were tested, and the results showed that they were 82% transferable across at least one species. The highest amplification rates were observed between the species from the Phaseolus (63.7%), Vigna (25.9%), Glycine (19.8%), Medicago (10.2%), Dipterix (6%) and Arachis (1.8%) genera. The average PIC (Polymorphism Information Content) varied from 0.53 for genomic SSRs to 0.47 for EST-SSRs, and the average number of alleles per locus was 4 and 3, respectively. Among the 315 newly tested SSRs in the BJ (BAT93 X Jalo EEP558) population, 24% (76) were polymorphic. The integration of these segregant loci into a framework map composed of 123 previously obtained SSR markers yielded a total of 199 segregant loci, of which 182 (91.5%) were mapped to 14 linkage groups, resulting in a map length of 1,157 cM. Conclusions: A total of 302 newly developed EST-SSR markers, showing good amplification quality, are available for the genetic analysis of Phaseolus vulgaris. These markers showed satisfactory rates of transferability, especially between species that have great economic and genomic values. Their diversity was comparable to genomic SSRs, and they were incorporated in the common bean reference genetic map, which constitutes an important contribution to and advance in Phaseolus vulgaris genomic research.Mostrar mais Item WebSat - a web software for microsatellite marker development(2009) Martins, Wellington Santos; Lucas, Divino César Soares; Neves, Kelligton Fabricio de Souza; Bertioli, David JohnMostrar mais Simple sequence repeats (SSR), also known as microsatellites, have been extensively used as molecular markers due to their abundance and high degree of polymorphism. We have developed a simple to use web software, called WebSat, for microsatellite molecular marker prediction and development. WebSat is accessible through the Internet, requiring no program installation. Although a web solution, it makes use of Ajax techniques, providing a rich, responsive user interface. WebSat allows the submission of sequences, visualization of microsatellites and the design of primers suitable for their amplification. The program allows full control of parameters and the easy export of the resulting data, thus facilitating the development of microsatellite markers.Mostrar mais Item Efficient BSP/CGM algorithms for the maximum subsequence sum and related problems(2015) Lima, Anderson Corrêa de; Branco, Rodrigo Gonçalves de; C´aceres, Edson Norberto; Gaioso, Roussian Di Ramos Alves; Aquino, Samuel Benjoino Ferraz; Song, Siang Wun; Martins, Wellington SantosMostrar mais Given a sequence of n numbers, with at least one positive value, the maximum subsequence sum problem consists in finding the contiguous subsequence with the largest sum or score, among all derived subsequences of the original sequence. Several scientific applications have used algorithms that solve the maximum subsequence sum. Particularly in Computational Biology, these algorithms can help in the tasks of identification of transmembrane domains and in the search for GC-content regions, a required activity in the operation of pathogenicity islands location. The sequential algorithm that solves this problem has O n time complexity. In this work we present BSP/CGM parallel algorithms to solve the maximum subsequence sum problem and three related problems: the maximum longest subsequence sum, the maximum shortest subsequence sum and the number of disjoints subsequences of maximum sum. To the best of our knowledge there are no parallel BSP/CGM algorithms for these related problems. Our algorithms use p processors and require O n/p parallel time with a constant number of communication rounds for the algorithm of the maximum subsequence sum and O log p communication rounds, with O n/p local computation per round, for the algorithm of the related problems. We implemented the algorithms on a cluster of computers using MPI and on a machine with GPU using CUDA, both with good speed-ups.Mostrar mais Item Software patterns: fundamentos, tipos e descrição(2003-12) Carvalho, Sérgio Teixeira deMostrar mais Specialists, in each project of software, acquire experience and knowledge that eventually are used in new projects. In the cases where good solutions are found, tested and applied, there are great possibilities for these methodologies are employed successfully in similar contexts. A software pattern describes in a standardized way a recurrent problem and presents a outline for its solution, making possible the reuse of the experience acquired in the solution of the problem. This article deals with the foundation of software patterns presenting its types and description.Mostrar mais Item Project Framework Model - PMF: um framework para o desenvolvimento de sistemas de informação orientados a objetos(2003-12) Branquinho, Leandro Doutor; Carvalho, Sérgio Teixeira deMostrar mais The object-oriented paradigm, when applied to development of information systems, offers resources that allow the construction of software for parts, analogous to the hardware. Each part corresponds to an object that is the responsible and the specialist in a service in the context of the information system. The oriented-object paradigm allows the development of systems more well organized with more quality. This article presents the PFM - Project Framework Model, a framework created to assist in the object-oriented information systems development, showing its classes, functioning, use and benefits, as well as its importance in the institution where it was developed and is being used. The article still presents a overview about object-oriented paradigm and frameworks.Mostrar mais Item Uso da programação orientada a aspectos em persistência de dados utilizando AspectJ(2007-12) Almeida, Leonardo Franco de; Duarte Júnior, Osvaldo Pereira; Carvalho, Sérgio Teixeira deMostrar mais This article has the objective to present a model of how aspect oriented programming can assist in solutions for data persistence using the language AspectJ. A general vision of aspect orientation is presented, the contexts in which aspect oriented programming languages are inserted and the use of aspects in the management of transactions involving data persistence.Mostrar mais Item Sistema de computação ubíqua na assistência domiciliar à saúde(2011-06) Carvalho, Sérgio Teixeira de; Copetti, Alessandro; Loques Filho, Orlando GomesMostrar mais through the integration of various services related to remote monitoring of a patient’s health. Method: analysis of the key experiences and work related to the area of ubiquitous computing in home care, together with the support from specialists in home care, with the aim of identifying the essential requirements that must be addressed for building a system of this class. Results: a system was implemented with a flexible architecture that integrates an infrastructure of sensors, devices, and intelligent services for (i) continuous identification of the patient’s health situation and sending alerts when appropriate, (ii) sending to patients notifications and reminders associated with the care plan, drawn up by health professionals. A prototype was implemented with a focus on processing blood pressure and heart rate data, and is presented as a demonstration of the feasibility of the proposed system. Conclusion: The proposed system implements integrated services that allow continuous monitoring of the evolution of patient at home.Mostrar mais Item Mecanismos de segurança da informação nas eleições brasileiras – estudo de caso sobre o pleito de 2010 em Goiás(2012) Magalhães, Thaís Domingues de; Carvalho, Sérgio Teixeira deMostrar mais The adoption of information technology in Brazilian Elections has brought greater security, speed and reliability. However, there is still suspicion and ignorance regarding all the technological support and tools that, when combined, ensure fairness in the voting process. This paper is aimed at analyzing how some of the information technology mechanisms used by the Brazilian Electoral Court contribute to achieve transparency and to ensure proper counting of votes, showing as case study the 2010 General Elections in the State of Goiás.Mostrar mais Item A new technique for verifying the consistency of distributed R-trees(2015-02) Oliveira, Sávio Salvarino Teles de; Souza Filho, José Ferreira de; Rodrigues, Vagner José do Sacramento; Cardoso, Marcelo de Castro; Carvalho, Sérgio TeixeiraMostrar mais The ever-increasing of spatial datasets and the widely application of the complex computation have motivated the emergence of distributed algorithms to process spatial operations efficiently. The R-tree index is broadly used by researches as a distributed spatial structure for indexing and retrieval of spatial objects. However, a big challenge has arisen, that is, how to check the consistency of distributed R-Trees. In the past few years researches have been published on both distributed R-Tree and verification of distributed systems. Though none of them has proposed a technique to check the consistency of distributed R-Trees. This article presents a new approach for verifying the consistency of distributed R-Trees, which is called RConsistency. It allows collect information about the distributed R-Tree once it has been created. RConsistency also collects information about the distribute R-Tree and can helps to reduce the overlapping and dead area. It can be used with any index similar to R-Tree, since the RConsistency algorithm uses the nodes organization of the R-Tree to collect consistency information. The algorithm was used on DistGeo, a platform to process distributed spatial operations. A graphic tool, named RConsistency Visualizer, was developed to show the output of the RConsistency algorithmMostrar mais Item The importance of word-final vowel duration for non-native portuguese speaker identification by means of support vector machines(2014) Franks, Suzanne; Barbosa, Rommel MelgaçoMostrar mais This article studies the acoustic characteristics of some oral vowels in tonic syllables of Brazilian Portuguese (BP) and which acoustic features are important for classifying native versus non-native speakers of BP. We recorded native and non-native speakers of BP for the purpose of the acoustic analysis of the vowels [a], [i], and [u] in tonic syllables. We analyzed the acoustic parameters of each segment using the Support Vector Machines algorithm to identify to which group, native or non-native, a new speaker belongs. When all of the variables were considered, a precision of 91% was obtained. The two most important acoustic cues to determine if a speaker is native or non-native were the durations of [i] and [u] in a word-final position. These findings can contribute to BP speaker identification as well as to the teaching of the pronunciation of Portuguese as a foreign language.Mostrar mais Item A characterisation of cubic parity graphs(2003) Barbosa, Rommel Melgaço; Ellingham, Mark NormanMostrar mais A graph is Zm-well-covered if all maximal independent sets have the same cardinality modulo m. Zm-well-covered graphs generalise well-covered graphs, those in which all independent sets have the same cardinality. Z2- well-covered graphs are also called parity graphs. A characterisation of cubic well-covered graphs was given by Campbell, Ellingham and Royle. Here we extend this to a characterisation of cubic Zm-well-covered graphs for all integers m ≥ 2; the most interesting case is m = 2, cubic parity graphs. Our main technique involves minimal non-well-covered graphs, and allows us to build our characterisation as an extension of the existing characterisation of cubic well-covered graphs.Mostrar mais Item Aplicação de técnicas de visão computacional para avaliar qualidade de radiografias odontológicas(2010) Costa, Ronaldo Martins da Costa; Patto, Vinícius Sebba; Souza, Rafael GomesMostrar mais The digitalization of images generated by x-rays, ultrasound scans, resonances and others have been popularized mainly due to the ease of access and low cost of devices that allow this operation. But incorrect digitalization can cause major disruptions and affect the diagnosis. In this paper we propose a computational methodology based on expert knowledge in radiology to assess computationally the quality of digitalized dental panoramic radiographs. Applying this methodology, it is possible to create techniques to ensure the quality of radiographic imaging.Mostrar mais

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