293 research outputs found
Envolvimento académico : confronto de expectativas e comportamentos em universitários do 1º ano
No presente trabalho analisam-se as expectativas dos estudantes acerca do
seu envolvimento em diversas dimensões associadas à vida académica, assim como
os comportamentos vivenciados uns meses após essa entrada tomando as mesmas
dimensões. A amostra considerada é formada por 314 estudantes do 1º ano de três
agrupamentos de cursos (Ciências e Engenharia; Ciências Económicas; e Ciências Sociais
e Humanas) da Universidade do Minho. Estes alunos responderam, no início do ano
e a meados do 2º semestre, ao Questionário de Envolvimento Académico (QEA; Soares
& Almeida, 2001) nas suas versões de expectativas (Versão A) e comportamentos
(Versão B). Os resultados sugerem níveis elevados de expectativas iniciais dos es-
tudantes no momento da sua entrada na Universidade, registando-se uma diminuição
significativa de tais índices no segundo momento da avaliação, em particular nas
subescalas de envolvimento institucional e de envolvimento vocacional. Algumas
oscilações nos resultados foram encontradas tomando os alunos de acordo com o
agrupamento do curso frequentado, com o género, os níveis escolares dos pais ou
o facto de frequentarem ou não um curso de 1º opção.This paper analyses students’ initial expectations concerning personal
investment in different domains of academic life, as well as behaviours some months
later in those same dimensions. The sample included 314 first year students of the
University of Minho from three graduations areas: science and engineering, economic
sciences, and social sciences and humanities. A questionnaire of academic involvement
(QEA; Soares & Almeida, 2001) was applied to students at entrance (expectations
version) and at middle of first semester (behaviours version). Results suggest higher
levels of initial expectations at the entrance in the university, and a significant decrease
of those levels some months later, namely in the institutional and vocational subscales.
Some significant changes have been found considering the domain and option of
graduation studies, gender and academic level of parents.Fundação Calouste Gulbenkian - Programa de Apoio a Projectos de Pesquisa no Domínio Educativo (2001/04) - projecto “Transição, adaptação e sucesso académico de jovens no Ensino Superior
Hyperfine magnetic field in ferromagnetic graphite
Information on atomic-scale features is required for a better understanding
of the mechanisms leading to magnetism in non-metallic, carbon-based materials.
This work reports a direct evaluation of the hyperfine magnetic field produced
at 13C nuclei in ferromagnetic graphite by nuclear magnetic resonance (NMR).
The experimental investigation was made possible by the results of
first-principles calculations carried out in model systems, including graphene
sheets with atomic vacancies and graphite nanoribbons with edge sites partially
passivated by oxygen. A similar range of maximum hyperfine magnetic field
values (18-21T) was found for all systems, setting the frequency span to be
investigated in the NMR experiments; accordingly, a significant 13C NMR signal
was detected close to this range without any external applied magnetic field in
ferromagnetic graphite
Music Segmentation and Similarity Estimation Applied to a Gaze-Controlled Musical Interface
Assistive technology, especially gaze-controlled, can promote accessibility, health care, well-being and inclusion for impaired people, including musical activities that can be supported by interfaces controlled using eye tracking. Also, the Internet growth has allowed access to a huge digital music database, which can contribute to a new form of music creation. In this paper, we propose the application of Music Information Retrieval techniques for music segmentation and similarity identification, aiming at the development of a new form of musical creation using an automatic process and the optimization algorithm Harmony Search to combine segments. These techniques for segmentation and similarity of segments were implemented in an assistive musical interface controlled by eye movement to support musical creation and well-being. The experimental results can be found in [https://bit.ly/2Zl7KSC]
Molecular Data Reveal Complex Hybridization and a Cryptic Species of Neotropical Wild Cat
SummaryHybridization among animal species has recently become more recognized as an important phenomenon, especially in the context of recent radiations [1–9]. Here we show that complex hybridization has led to contrasting patterns of genomic composition among closely related species of the Neotropical cat genus Leopardus. We show strong evidence of ancient hybridization and introgression between the pampas cat (L. colocolo) and northeastern populations of tigrina (L. tigrinus), leading to remarkable cytonuclear discordance in the latter. In contrast, southern tigrina populations show recent and continuing hybridization with Geoffroy’s cat (L. geoffroyi), leading to extreme levels of interspecific admixture at their contact zone. Finally, we demonstrate that two seemingly continuous Brazilian tigrina populations show no evidence of ongoing gene flow between them, leading us to support their formal recognition as distinct species, namely L. tigrinus in the northeast and L. guttulus in the south
Cyanobacteria and Cyanotoxin in the Billings Reservoir (Sâo Paulo, SP, Brazil)
The Billings Complex and the Guarapiranga System are important strategic reservoirs for the city of Sâo Paulo and surrounding areas because the water is used, among other things, for the public water supply. They produce 19,000 liters of water per second and supply water to 5.4 million people. Crude water is transferred from the Taquacetuba branch of the Billings Complex to the Guarapiranga Reservoir to regulate the water level of the reservoir. The objective of this study was to evaluate the water quality in the Taquacetuba branch, focusing on cyanobacteria and cyanotoxins. Surface water samples were collected in February (summer) and July (winter) of 2007. Analyses were conducted of physical, chemical, and biological variables of the water, cyanobacteria richness and density, and the presence of cyanotoxins. The water was classified as eutrophic-hypereutrophic. Cyanobacteria blooms were observed in both collection periods. The cyanobacteria bloom was most significant in July, reflecting lower water transparency and higher levels of total solids, suspended organic matter, chlorophyll-a, and cyanobacteria density in the surface water. Low richness and elevated dominance of the cyanobacteria were found in both periods. Cylindrospermopsis raciborskii was dominant in February, with 352 661.0 cel mL−1, and Microcystis panniformis was dominant in July, with 1 866 725.0 cel mL−1. Three variants of microcystin were found in February (MC-RR, MC-LR, MC-YR), as well as saxitoxin. The same variants of microcystin were found in July, but no saxitoxin was detected. Anatoxin-a and cylindropermopsin were not detected in either period. These findings are of great concern because the water in the Taquacetuba branch, which is transferred into the Guarapiranga Reservoir, is not treated nor managed. It is recommended that monitoring be intensified and more effective measures be taken by the responsible agencies to prevent the process of eutrophication and the consequent development of the cyanobacteria and their toxinsEl Complejo Billings y el Sistema Guarapiranga son embalses estratégicos importantes para la ciudad de Sâo Paulo (Brasil) y áreas circundantes porque, entre otras cosas, el agua es utilizada para el abastecimiento público. Este sistema produce 19 mil litros de agua por segundo, que es suministrado a 5.4 millones de personas. El agua bruta es transferida por el afluente Taquacetuba desde el Complejo Billings hacia el Embalse Guarapiranga, para regular el nivel de agua del embalse. El objetivo de este estudio fue evaluar la calidad del agua en el tramo del Taquacetuba, teniendo como foco las cianobacterias y cianotoxinas. El muestreo de agua bruta superficial fue realizado en febrero (verano) y julio (invierno 2007). Fueron analizadas variables físicas, químicas y biológicas, cianobacteria, riqueza, densidad y la presencia de cianotoxinas. El tramo fue clasificado como eutrófico-hipereutrófico. Las cianobacterias fueron observadas en ambos periodos de colecta. El crecimiento más significativo de algas fue observado en julio, reflejando baja transparencia del agua y niveles más altos en el agua superficial de sólidos totales, materia orgánica, clorofila-a y densidad de cianobacterias en el agua superficial. Una baja riqueza y un elevado dominio de cianobacteria fueron encontrados en ambos períodos. Cylindrospermopsis raciborskii fue dominante en febrero, con 352 661.0 cel mL�1, y Microcystis panniformis fue dominante en julio, con 1 866 725.0 cel mL�1. Tres variedades de microcistina fueron encontradas en febrero (MC-RR, MC-LR, MC- YR), as� como saxitoxina. Las mismas variedades de microcistina fueron encontradas en julio, pero ninguna saxitoxina fue observada. Anatoxina-a y cylindropermopsina no fueron observadas en ningún período. Estas conclusiones son preocupantes porque el agua del tramo del Taquacetuba, que es transferida al Embalse Guarapiranga, no es tratada o manejada. Se recomienda intensificar el monitoreo y medidas más eficaces deben ser tomadas por parte de las agencias responsables para prevenir el proceso de eutrofización y el desarrollo consiguiente de cianobacterias y sus toxina
Detrimental Effect Of Fungal 60-kda Heat Shock Protein On Experimental Paracoccidioides Brasiliensis Infection
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The genus Paracoccidioides comprises species of dimorphic fungi that cause paracocci-dioidomycosis (PCM), a systemic disease prevalent in Latin America. Here, we investigated whether administration of native 60-kDa heat shock protein of P. brasiliensis (nPbHsp60) or its recombinant counterpart (rPbHsp60) affected the course of experimental PCM. Mice were subcutaneously injected with nPbHsp60 or rPbHsp60 emulsified in complete's Freund Adjuvant (CFA) at three weeks after intravenous injection of P. brasiliensis yeasts. Infected control mice were injected with CFA or isotonic saline solution alone. Thirty days after the nPbHsp60 or rPbHsp60 administration, mice showed remarkably increased fungal load, tissue inflammation, and granulomas in the lungs, liver, and spleen compared with control mice. Further, rPbHsp60 treatment (i) decreased the known protective effect of CFA against PCM and (ii) increased the concentrations of IL-17, TNF-alpha, IL-12, IFN-gamma, IL-4, IL-10, and TGF-beta in the lungs. Together, our results indicated that PbHsp60 induced a harmful immune response, exacerbated inflammation, and promoted fungal dissemination. Therefore, we propose that PbHsp60 contributes to the fungal pathogenesis.119Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [2009/14777-1, 2013/12278-3, 2009/03235-3, 2012/08552-0]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Doses e formas de aplicação da adubação potássica na rotação soja, milheto e algodão em sistema plantio direto.
Este estudo teve como objetivo avaliar a eficiência da adubação potássica, com relação às doses, modos (sulco, a lanço e parcelada) e épocas de aplicação (pré-semeadura, semeadura e cobertura), na sucessão de culturas soja-milheto-algodoeiro, cultivadas em sistema plantio direto, em Latossolo Vermelho, no município de Turvelândia, Goiás (17o51?S, 50o18?W). O delineamento experimental adotado foi o de blocos casualizados, com quatro repetições, em esquema fatorial. A fonte de potássio utilizada nas adubações foi o cloreto de potássio. Na soja, os tratamentos utilizados foram doses de K2O (0 kg ha-1, 30 kg ha-1, 60 kg ha-1 e 180 kg ha-1), aplicadas em pré-semeadura (a lanço) e na semeadura (no sulco), com e sem cobertura. Na cultura do algodoeiro, os tratamentos foram doses de K2O (0 kg ha-1, 60 kg ha-1, 120 kg ha-1 e 240 kg ha-1), aplicadas em pré-semeadura (a lanço) e na semeadura (no sulco), com 0, 1 ou 2 coberturas. A adubação em pré-semeadura foi realizada no milheto. Não houve efeito da adubação potássica sobre a produtividade da cultura da soja. O milheto, como cobertura do solo, aproveitou, mais eficientemente, a dose de 60 kg ha-1 de K2O, aplicada na cultura da soja. Para a cultura do algodoeiro, a maior eficiência agronômica foi obtida com dose de 146 kg ha-1 de K2O, em pré-semeadura. Os resultados indicaram, também, que houve efeito positivo da adubação potássica sobre a qualidade da fibra do algodão
Estudo da força de tração utilizando parafuso excêntrico em Placa de Compressão Dinâmica Larga (DCP-L)
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