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Publicações - ciências exatas e da terra

Impact of Tdap vaccine during pregnancy on the incidence of pertussis in children under one year in Brazil ? A time series analysis Clarice Paiva Santana; Karin Regina Luhm; EMIKO SHIMAKURA, SILVIA VACCINE, v. 1, p. 1 2021 DOI Home page Palavra-chave: Pertussis; Tdap vaccine; Vaccination in pregnancy Áreas do conhecimento: Ciências da Saúde; Saúde Coletiva; Epidemiologia; Ciências Exatas e da Terra; Probabilidade e Estatística; Probabilidade e Estatística Aplicadas; Análise de Dados Longitudinais resumo ...
Improving Barnes-Hut t-SNE Algorithm in Modern GPU Architectures with Random Forest KNN and Simulated Wide-Warp MEYER, BRUNO HENRIQUE; Aurora Trinidad Ramirez Pozo; ZOLA, WAGNER M. NUNAN ACM Journal on Emerging Technologies in Computing Systems, v. 17, n. 4, p. 1-26, 2021 DOI Palavra-chave: Aprendizado de Maquina; ciência da computação; GPU Áreas do conhecimento: Ciências Exatas e da Terra; Metodologia e Técnicas da Computação; Inteligencia Artificial resumo ... The t-Distributed Stochastic Neighbor Embedding (t-SNE) is a widely used technique for dimensionality reduction but is limited by its scalability when applied to large datasets. Recently, BH-tSNE w...
Insecticidal and oviposition deterrent effects of essential oils of Baccharis spp. and histological assessment against Drosophila suzukii (Diptera: Drosophilidae) DE SOUZA, MICHELE TROMBIN; DE SOUZA, MIRELI TROMBIN; BERNARDI, DANIEL; DE MELO, DOUGLAS JOSÉ; Paulo Henrique Gorgatti Zarbin; Maria Aparecida Cassilha Zawadneak Scientific Reports, v. 11, n. 1, p. n/a 2021 DOI Palavra-chave: ecologia química; fitoquímica Áreas do conhecimento: Ciências Exatas e da Terra; Química; Química Orgânica; Evolução, Sistemática e Ecologia Química resumo ... The diverse flora of the Atlantic Forest is fertile ground for discovering new chemical structures with insecticidal activity. The presence of species belonging to the genus Baccharis is of particular interest, as these species have shown promise in pest management applications. The objective of this study is to chemically identify the constituents expressed in the leaves of seven species of Baccharis (B. anomala DC., B. calvescens DC., B. mesoneura DC., B. milleflora DC., B. oblongifolia Pers., B. trimera (Less) DC. and B. uncinella DC.) and to evaluate the toxicological and morphological effects caused by essential oils (EOs) on the larvae and adults of Drosophila suzukii (Diptera: Drosophilidae). Chemical analysis using gas chromatography-mass spectrometry (GC–MS) indicated that limonene was the main common constituent in all Baccharis species. This constituent in isolation, as well as the EOs of B. calvescens, B. mesoneura, and B. oblongifolia, caused mortality in over 80% of adults of D. suzukii at a discriminatory concentration of 80 mg L−1 in bioassays of ingestion and topical application. These results are similar to the effect of spinosyn-based synthetic insecticides (spinetoram 75 mg L−1) 120 h after exposure. Limonene and EOs from all species had the lowest LC50 and LC90 values relative to spinosyn and azadirachtin (12 g L−1) in both bioassays. However, they showed the same time toxicity over time as spinetoram when applied to adults of D. suzukii (LT50 ranging from 4.6 to 8.7 h) in a topical application bioassay. In olfactometry tests, 92% of D. suzukii females showed repellent behavior when exposed to the EOs and limonene. Likewise, the EOs of B. calvescens, B. mesoneura, and B. oblongifolia significantly reduced the number of eggs in artificial fruits (≅ 7.6 eggs fruit−1), differing from the control treatment with water (17.2 eggs fruit−1) and acetone (17.6 eggs fruit−1). According to histological analyses, the L3 larvae of D. suzukii had morphological and physiological alterations and deformations after exposure to treatments containing EOs and limonene, which resulted in high larval, pupal, and adult mortality. In view of the results, Baccharis EOs and their isolated constituent, limonene, proved to be promising alternatives for developing bioinsecticides to manage of D. suzukii.
Insights on the influence of phylogenetic in the relative growth using Atherinella brasiliensis (Quoy and Gaimard 1824) as a tool Renato Luis Bot Neto; Barbara Maichak de Carvalho; Roberto Schwarz Jr; Henry Louis Spach BOLETIM DO INSTITUTO DE PESCA, v. 41, p. 1-9, 2021 DOI Palavra-chave: age; fish growth; development Áreas do conhecimento: Ciências Exatas e da Terra; Oceanografia Biológica; Interação entre os Organismos Marinhos e os Parâmetros Ambientais resumo ... (en) The lengthí weight relationships (LWR) are important tools for ichthyology, they are useful to demonstrate the environmental influence on growth. In this study we estimate the LWR of the Atherinella brasiliensis in the shallow areas of the São Francisco river estuary and compare the growth of this specie in different environments of the Brazilian coast. Specimens of Brazilian silverside (A. brasiliensis, n = 3483), between 2.1 and 13.6 cm in length, were caught in the shallow areas of the São Francisco River estuary between May 2017 and April 2018. The length-weight ratio of the species was represented by the equation y=0.0047x3.0913. Frequency distribution indicates that the species is present in the shallow areas of the São Francisco River estuary in all its ontogenetic stages and apparently reproduces throughout the year with constant input of recruits into the population. Von Bertalanffyââ‚¬â„¢s growth model and longevity were adjusted to reach asymptotic length (LâË†Å¾) of 14.7 cm, growth coefficient (K) of 0.91 year-1 and longevity (A95) of 3.25 years. The analysis of variance revealed differences for the maximum total length. However, the differences found between the present study and data available in the literature appear to be caused by environmental and methodological differences. (pt) As relações peso-comprimento (LWR) são ferramentas importantes para a ictiologia, são úteis para demonstrar a influência ambiental no crescimento. Neste estudo estimamos o LWR de Atherinella brasiliensis em áreas rasas do estuário do rio São Francisco e comparamos o crescimento desta espécie em diferentes ambientes do litoral brasileiro. Espécimes do peixe-rei (A. brasiliensis, n = 3483), entre 2,1 e 13,6 cm de comprimento, foram capturados nas áreas rasas do estuário do rio São Francisco entre maio de 2017 e abril de 2018. A relação peso-comprimento das espécies foi representada por a equação y=0.0047x3.0913. A distribuição de frequência indica que a espécie está presente nas áreas rasas do estuário do rio São Francisco em todos os seus estágios ontogenéticos e aparentemente se reproduz ao longo do ano com entrada constante de recrutas na população. Os modelos de crescimento e longevidade de Von Bertalanffy foram ajustados para atingir comprimento assintótico (LâË†Å¾) de 14,7 cm, coeficiente de crescimento (K) de 0,91 ano-1 e longevidade (A95) de 3,25 anos. A análise de varií¢ncia revelou diferenças para o comprimento total máximo. No entanto, as diferenças encontradas entre o presente estudo e os dados disponíveis na literatura parecem ser causadas por diferenças ambientais e metodológicas.
Intercalation of anionic organic ultraviolet absorbers in bimetallic and trimetallic layered double hydroxides for low-density polyethylene protection Neffer Arvey Gomez Gomez; Gabriel Machado Silva; WYPYCH, FERNANDO POLYMER BULLETIN, v. 1, p. 1-18, 2021 DOI Palavra-chave: Polymer-matrix composites; Degradation; layered double hydroxide Áreas do conhecimento: Ciências Exatas e da Terra; Química; Química Orgânica; Polímeros e Colóides resumo ... Bimetallic (Zn/Al) and trimetallic (Mg,Zn/Al) layered double hydroxides (LDHs) intercalated with nitrate were synthesized by the coprecipitation method and used as precursors to obtain LDHs intercalated with the organic anions 4–4′-diamino-2,2′-stilbenedisulfonate and ortho-phthalate through anion exchange reactions. The materials were used as fillers in different ratios in low-density polyethylene (LDPE) to obtain polymer nanocomposites by extrusion-injection molding. The layered materials were characterized by several instrumental techniques, and the mechanical properties of the nanocomposites were evaluated. The samples were exposed to thermo-oxidative conditions at 60 and 90 °C for 1194 h, and the degradation process of the polymer nanocomposites was studied by measurements of hardness, weight loss and oxidation index. Results showed that trimetallic and bimetallic LDH had a notable effect on the LDPE nanocomposites’ degradation, depending on the intercalated anion. Both systems showed potential use as environmentally friendly stabilizers of polymeric matrices, reducing material damage induced by heat and oxidation, increasing the lifetime of the material and lowering the environmental impact.
Interplay between magnetic moment and magnetocrystalline anisotropy in tetragonally distorted galfenol films C. DE OLIVEIRA, R.; Z. C. PAES, V.; H. MOSCA, D.; José Varalda JOURNAL OF APPLIED PHYSICS, v. 129, n. 17, p. 173902 2021 DOI Palavra-chave: FeGa; Galfenol; Magnetic moment; magnetocrystalline anisotropy Áreas do conhecimento: Ciências Exatas e da Terra; Física; Física da Matéria Condensada; Ciências Exatas e da Terra; Física; Física da Matéria Condensada; Materiais Magnéticos e Propriedades Magnéticas resumo ... Magnetic properties of Fe100−xGax (x = 15 and 30) epitaxial thin films on GaAs(001) substrates were studied experimentally and theoretically. The samples grown by molecular beam epitaxy under certa...
Investigating Automatic Parameter Tuning for SQL-on-Hadoop Systems Edson Ramiro Lucas Filho; Eduardo Cunha de Almeida; Steffanie Scherzinger; Herodotos Herodoto Big Data Research, p. 100204 2021 DOI Palavra-chave: BigData; SQL-on-Hadoop; MapReduce Áreas do conhecimento: Ciências Exatas e da Terra; Ciência da Computação; Metodologia e Técnicas da Computação; Banco de Dados resumo ...
Jeans instability from post-Newtonian Boltzmann equation Gilberto Medeiros Kremer EUROPEAN PHYSICAL JOURNAL C, v. 81, n. 10, p. 927 2021 DOI Palavra-chave: Instabilidade de Jeans; Equacao de Boltzmann Áreas do conhecimento: Ciências Exatas e da Terra; Física Geral; Relatividade e Gravitação; Ciências Exatas e da Terra; Física; Física Geral; Física Estatística e Termodinâmica resumo ... Jeans instability within the framework of post-Newtonian Boltzmann and Poisson equations are analyzed. The components of the energy–momentum tensor are calculated from a post-Newtonian Maxwell-Jüttner distribution function. The perturbations of the distribution function and gravitational potentials from their background states with the representation of the perturbations as plane waves lead to a dispersion relation with post-Newtonian corrections. The influence of the post-Newtonian approximation on the Jeans mass is determined and it was shown that the mass necessary for an overdensity to begin the gravitational collapse in the post-Newtonian theory is smaller than the one in the Newtonian theory.
Laplacian integral graphs with a given degreee sequence constraint NOVANTA, ANDERSON FERNANDES; Carla Oliveira; Leonardo Silva de Lima PROYECCIONES JOURNAL OF MATHEMATICS, v. 40, n. 6, p. 1431-1448, 2021 DOI Home page Palavra-chave: Laplacian integral graphs; spectral graph theory; eigenvalues Áreas do conhecimento: Engenharias; Engenharia Elétrica; Telecomunicações; Ciências Exatas e da Terra; Matemática; Matemática Aplicada; Física Matemática resumo ... (en) Let G be a graph on n vertices. The Laplacian matrix of G, denoted by L(G), is defined as L(G) = D(G) − A(G), where A(G) is the adjacency matrix of G and D(G) is the diagonal matrix of the vertex degrees of G. A graph G is said to be L-integral is all eigenvalues of the matrix L(G) are integers. In this paper, we characterize all L-integral non-bipartite graphs among all connected graphs with at most two vertices of degree larger than or equal to three.
Linear flows on compact, semisimple Lie groups: stability and periodic orbits Simão Nicolau Stelmastchuk Electronic Journal of Qualitative Theory of Differential Equations, v. 84, p. 1-12, 2021 Home page Palavra-chave: Stability; periodic orbits; linear flows; semisimple Lie groups Áreas do conhecimento: Ciências Exatas e da Terra; Análise; Equações Diferenciais Ordinárias resumo ...

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