21 research outputs found

    Quantum Mechanical Approaches for Piezoelectricity Study in Perovskites

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    In this chapter, we show the procedures we have been used to theoretically investigate the piezoelectric effects in perovskites. The construction of extended basis sets using the generator coordinate Hartree-Fock (GCHF) method is shown, as well as the strategies used to contract extended basis sets and to evaluate their quality in molecular calculations. Besides, we show adequate procedures to choice polarization and diffuse functions to best represent the studied crystal. In addition, we also discuss conditions under which GCHF basis sets and standard basis sets from literature can be used to theoretical investigation of piezoelectricity in perovskites. We finalize the chapter presenting and discussing the results for investigations of piezoelectricity with standard basis sets for barium and lanthanum titanates. To conclude, we present evidences that BaTiO3 and LaTiO3 may have piezoelectric properties caused by electrostatic interactions

    Molecular Electrostatic Potential and Chemometric Techniques as Tools to Design Bioactive Compounds

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    In this chapter, firstly, we briefly review aspects of the approximation of quantum chemistry, molecular electrostatic potential (MEP), and chemometrics techniques, which are accredited as important tools in the development of chemical science and are frequently used in the study and design of bioactive compounds. Ultimately, we use MEP and pattern recognition (PR) techniques as tools to design nitrofuran compounds with biological activity against Trypanosoma cruzi (T. cruzi). PR models (PCA, HCA, KNN, SDA, and SIMCA) were constructed and demonstrated that 23 nitrofurans can be classified into two classes or groups: more active and less active according to their degrees of activity against T. cruzi. Properties such as charge on the N atom of the nitro group (QN1); the difference between the highest occupied molecular orbital (HOMO) energy and the lowest unoccupied molecular orbital (LUMO) energy (GAP energy); molecular representation of structure based on electron diffraction code of signal 5, unweighted (Mor05u); and Moriguchi water–octanol partition coefficient (MlogP) are responsible for the classification into more active and less active studied nitrofurans. It is interesting to notice that these properties represent three distinct classes of interactions between the nitrofurans and the biological receptor: electronic (QN1 and GAP energy), steric (Mor05u), and hydrophobic (MlogP). The results of the application of PR models on the validation set evidenced two nitrofuran compounds (compounds 25 and 30) as more promising for synthesis and biological assays, which in the future can be used to validate our PR models

    Gonad development and sperm characteristics of male silver catfish (Rhamdia quelen) fed diets with different oil sources / Desenvolvimento gonadal e características espermáticas de jundiás machos (Rhamdia quelen) alimentados com dietas com diferentes fontes de óleo

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    It is widely accepted that broodstock nutrition or enriched diets with certain compounds greatly impacts fish reproductive performance, especially the input of different concentrations of fatty acids (especially polyunsaturated ones). Thus, here we evaluated  reproductive variables in male catfish (Rhamdia quelen) of 18.45 ± 1.22 g fed with diets containing different lipid sources: fish, canola, sunflower, soybean and olive oils. 300 juvenile R. quelen were randomly distributed in 20 net-tanks (1m3) disposed inside a 200 m2 masonry pond, and the experiment was composing five treatments with four replicates, and were fed during 90 days, with a 3% inclusion level of the oils in the diets. The histological evaluations of the fish testicles were characterized in the final development stage and maturation in all animals, regardless of the offered diet. Spermatic normality, seminal volume, total sperm production, seminal pH and testosterone level did not present significant differences among treatments. Higher sperm concentration was more pronounced in males fed a diet containing sunflower oil. Parameters obtained by computer-assisted sperm analysis (CASA) showed that the poor sperm quality were verify when fish were fed diets containing olive and canola oil. The gonadosomatic, hepatosomatic and viscerosomatic fat indexes of the animals were similar, regardless of the supplied lipid source. In a practical perspective, we concluded that soybean and sunflower oils can be used as replacement to fish oil in diets for male specimens of R. quelen while the canola and olive oils should be avoid, because decrease the sperm quality

    Survivorship of Anopheles darlingi (Diptera: Culicidae) in Relation with Malaria Incidence in the Brazilian Amazon

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    We performed a longitudinal study of adult survival of Anopheles darlingi, the most important vector in the Amazon, in a malarigenous frontier zone of Brazil. Survival rates were determined from both parous rates and multiparous dissections. Anopheles darlingi human biting rates, daily survival rates and expectation of life where higher in the dry season, as compared to the rainy season, and were correlated with malaria incidence. The biting density of mosquitoes that had survived long enough for completing at least one sporogonic cycle was related with the number of malaria cases by linear regression. Survival rates were the limiting factor explaining longitudinal variations in Plasmodium vivax malaria incidence and the association between adult mosquito survival and malaria was statistically significant by logistic regression (P<0.05). Survival rates were better correlated with malaria incidence than adult mosquito biting density. Mathematical modeling showed that P. falciparum and P. malariae were more vulnerable to changes in mosquito survival rates because of longer sporogonic cycle duration, as compared to P. vivax, which could account for the low prevalence of the former parasites observed in the study area. Population modeling also showed that the observed decreases in human biting rates in the wet season could be entirely explained by decreases in survival rates, suggesting that decreased breeding did not occur in the wet season, at the sites where adult mosquitoes were collected. For the first time in the literature, multivariate methods detected a statistically significant inverse relation (P<0.05) between the number of rainy days per month and daily survival rates, suggesting that rainfall may cause adult mortality

    Paraganglioma timpânico: a propósito de dois casos Tympanic paraganglioma: two cases

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    Universidade Federal de São Paulo (UNIFESP)Hospital do Servidor Público Estadual de São Paulo Serviços de OtorrinolaringologiaHospital do Servidor Público Municipal de São Paulo Serviços de OtorrinolaringologiaSanta Casa de São Paulo Faculdade de Ciências Médicas programa de Pós-graduação em OtorrinolaringologiaHSPM Serviço de OtorrinolaringologiaPUCUNIFESPSciEL

    Preclinical randomized controlled trial of bilateral discectomy versus bilateral discopexy in Black Merino sheep temporomandibular joint: TEMPOJIMS – Phase 1- histologic, imaging and body weight results

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    © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.The role of temporomandibular joint (TMJ) surgery is not well defined due to a lack of quality randomized controlled clinical trials, comparing different TMJ surgical treatments with medical and placebo interventions. The temporomandibular joint interposal study (TEMPOJIMS) is a rigorous preclinical trial divided in 2 phases. In phase 1 the authors investigated the role of the TMJ disc and in phase 2 the authors evaluated 3 different interposal materials. The present work of TEMPOJIMS - phase 1, aims to evaluate histopathologic and imaging changes of bilateral discectomy and discopexy in Black Merino sheep TMJ, using a high-quality trial following the ARRIVE guidelines.info:eu-repo/semantics/publishedVersio
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