Background Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is a serious public hea... more Background Chagas disease (CD), caused by the parasite Trypanosoma cruzi, is a serious public health concern in Latin America. Nifurtimox and benznidazole (BZ), the only two drugs currently approved for the treatment of CD, have very low efficacies in the chronic phase of the disease and several toxic side effects. Trypanosoma cruzi strains that are naturally resistant to both drugs have been reported. We performed a comparative transcriptomic analysis of wild-type and BZ-resistant T. cruzi populations using high-throughput RNA sequencing to elucidate the metabolic pathways related to clinical drug resistance and identify promising molecular targets for the development of new drugs for treating CD. Methods All complementary DNA (cDNA) libraries were constructed from the epimastigote forms of each line, sequenced and analysed using the Prinseq and Trimmomatic tools for the quality analysis, STAR as the aligner for mapping the reads against the reference genome (T. cruzi Dm28c—2018), ...
In this paper we study the distribution of totients 2 mod.4. We prove that the asymptotic magnitu... more In this paper we study the distribution of totients 2 mod.4. We prove that the asymptotic magnitude of such totients with multiplicity two is half of that of prime numbers. As a corollary we obtain that the relative asymptotic density of the number of those totients with multiplicity four over the number of totients with multiplicity two is zero. We also obtain that the set of totients with multiplicity k > 1 which have power, bigger than one, of a prime in their pre-images has relative asymptotic density zero over the number of all totients of multiplicity k. A result on the distribution of consecutive pairs of totients 2 mod.4, which relates to cousin primes, is also provided. 2010 Mathematics Subject Classification. 11A25 and 11N64.
We prove that, for every k ≥ 4, the sets M (k) and L(k), which are Markov and Lagrange dynamical ... more We prove that, for every k ≥ 4, the sets M (k) and L(k), which are Markov and Lagrange dynamical spectra related to conservative horseshoes and associated to continued fractions with coefficients bounded by k coincide with the intersections of the classical Markov and Lagrange spectra with (−∞, √ k 2 + 4k]. We also observe that, despite the corresponding statement is also true for k = 2, it is false for k = 3.
We construct four new elements 3.11>m_1>m_2>m_3>m_4 of M L lying in distinct connecte... more We construct four new elements 3.11>m_1>m_2>m_3>m_4 of M L lying in distinct connected components of R∖ L, where M is the Markov spectrum and L is the Lagrange spectrum. These elements are part of a decreasing sequence (m_k)_k∈N of elements in M converging to 3 and we give some evidence towards the possibility that m_k∈ M∖ L for all k≥ 1. In particular, this indicates that 3 might belong to the closure of M∖ L, so that the answer to Bousch's question about the closedness of M∖ L might be negative.
Bulletin of the Brazilian Mathematical Society, New Series, 2021
In this paper we study the multiplicities and the asymptotic behaviour of the numbers of totients... more In this paper we study the multiplicities and the asymptotic behaviour of the numbers of totients in the strata given by 2-adic valuation. 2010 Mathematics Subject Classification. 11A25 and 11N64.
O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilida... more O conteúdo dos artigos e seus dados em sua forma, correção e confiabilidade são de responsabilidade exclusiva dos seus respectivos autores.
Annales de l'Institut Henri Poincaré C, Analyse non linéaire, 2021
The Markov and Lagrange dynamical spectra, introduced by Moreira, share several geometric and top... more The Markov and Lagrange dynamical spectra, introduced by Moreira, share several geometric and topological aspects with the classical ones. However, some features of generic dynamical spectra associated to hyperbolic sets can be proved in the dynamical case and we do not know if they are true in classical case. They can be a good source of natural conjectures about the classical spectra: it is natural to conjecture that some properties which hold for generic dynamical spectra associated to hyperbolic maps also holds for the classical Markov and Lagrange spectra. In this thesis we show that, for generic dynamical spectra associated to horseshoes, there is a transition point a in the spectra such that for any δ > 0, the intersection of the spectra with (a−δ, a) is a countable union of Cantor sets with Hausdorff dimension smaller than 1, while the intersection of the spectra with (a, a + δ) have non-empty interior. This is still open for the classical Markov and Lagrange spectra.
Background: One of the major challenges for leishmaniasis treatment is the emergence of parasites... more Background: One of the major challenges for leishmaniasis treatment is the emergence of parasites resistant to antimony. In order to study differentially expressed genes associated with drug resistance we performed a comparative transcriptomic analysis between wild-type and potassium antimonyl tartrate (SbIII)-resistant Leishmania infantum lines using high-throughput RNA sequencing.Methods: All the cDNA libraries were constructed from promastigote forms of each line, sequenced and analyzed using STAR for mapping the reads against the reference genome (L. infantum JPCM5) and DESeq2 for differential expression statistical analyses. All the genes were functionally annotated using sequence similarity search.Results: The analytical pipeline considering an adjusted p-value lower than 0.05 and fold change greater than 2.0 identified 933 transcripts differentially expressed (DE) between wild-type and SbIII-resistant L. infantum lines. Out of 933 DE transcripts, 504 presented functional anno...
We show that $1+3/\sqrt{2}$ is a point of the Lagrange spectrum $L$ that is accumulated by a sequ... more We show that $1+3/\sqrt{2}$ is a point of the Lagrange spectrum $L$ that is accumulated by a sequence of elements of the complement $M\!\setminus\! L$ of the Lagrange spectrum in the Markov spectrum $M$. In particular, $M\!\setminus\! L$ is not a closed subset of $\mathbb{R}$, so that a question by T. Bousch has a negative answer.
O objetivo deste trabalho é desenvolver o conceito de Business Intelligence aplicado ao processo ... more O objetivo deste trabalho é desenvolver o conceito de Business Intelligence aplicado ao processo de Business Performance Management, utilizando uma abordagem fenomenológica de pesquisa. Partindo do desenvolvimento dos conceitos apresentados em diversos artigos e livros, aliado ao estudo de três casos selecionados, pretende-se caracterizar a utilização do referido instrumento como um valioso suporte ao processo de gestão empresarial com foco em medidas de resultado. Palavras-chave: Business intelligence. Medidas de desempenho. Controle gerencial. 1 Introdução No atual cenário de negócios, a diferenciação e a busca por um desempenho de destaque, seja a empresa de que ramo for, dar-se-ão por meio da utilização de recursos que visam à execução ótima das atividades, em paralelo à redução de seus custos. Por intermédio dos elementos da tecnologia de informação, é possível armazenar e acessar de maneira eficaz e estruturada, informações sobre fornecedores, clientes e suas tendências de consumo, concorrentes e demais elementos de gestão da própria empresa, além de viabilizar a interlocução dos participantes, bem como a análise dos dados obtidos, no sentido de operar de maneira segura e objetiva.
We apply a recent functional analytic approach to obtain statistical properties of a class of Ran... more We apply a recent functional analytic approach to obtain statistical properties of a class of Random Dynamical Systems. More precisely, we prove that its invariant measure has a Lipschitz disintegration. As a consequence, exponential decay of correlations over regular observables is obtained. Both results are reached as an application of a spectral gap for its transfers operator.
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