1,252 research outputs found

    Social factors associated to binge drinking: a cross-sectional survey among Brazilian students in private high schools

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    <p>Abstract</p> <p>Background</p> <p>Binge drinking (BD) seems to be related to health and social complications among adolescents. Considering that knowledge about BD in developing countries is limited and that in Brazil high socioeconomic status is a risk factor for alcohol abuse, this study sheds light about this phenomenon among adolescents from a different cultural background than prior North-American and European studies.</p> <p>Methods</p> <p>Brazilian students (n = 2691) selected through a representative, stratified and clustered sampling method were asked to answer a self-report questionnaire. The questionnaire contained questions about patterns of alcohol consumption, religious beliefs, leisure activities, family structure and relationships. Data were analyzed with basic contingency tables with Chi-square tests followed by a decision tree analysis and weighted logistic regression.</p> <p>Results</p> <p>Almost thirty-five percent of the students reported recent binge drinking. BD in the past month was positively associated with older age (aOR = 1.5[1.2-1.7]), male gender (aOR = 1.5[1.2-2.0]) going out with friends almost every night (aOR = 33.9[14.2-80.7]), not living with mother (aOR = 2.4[1.3-4.7]), believing in God with little conviction (aOR = 1.6[1.2-2.0]) and rarely talking to parents about anything (aOR = 1.7[1.3-2.2]) or always about drugs (aOR = 1.8[1.3-2.5]). Factors inversely associated with BD were: paying lower monthly tuition fees (aOR = 0.5[0.4-0.9]), living with people who do not get drunk (aOR = 0.6[0.4-0.7]) and frequent engagement in worships (aOR = 0.7[0.5-0.9]).</p> <p>Conclusion</p> <p>The habit of BD in adolescents enrolled in private high schools in Brazil is strongly linked to the frequency with which they go out with friends at night. Factors such as religiosity, expressed by trust in God and participation in worship, and being enrolled in a school with cheaper tuition fees were associated with avoidance of BD in this population.</p

    A caminho de um ambiente adaptativo de aprendizagem baseado no nível de aquisição de conhecimentos do estudante

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    A grande maioria dos Sistemas de Gerenciamento de Aprendizagem predominantemente em uso no ensino com suporte computacional são estáticos e lineares, ou seja, apresentam o mesmo conteúdo instrucional para os diversos estudantes sem considerar o nível de aquisição de conhecimentos de cada um. Isso torna esses ambientes muitas vezes desestimulantes para estudantes que estão num nível mais avançado e inibidores para aqueles que estão num nível ainda inicial. Este artigo tem por objetivo apresentar o modelo de funcionamento de um ambiente computacional de aprendizagem baseado no nível de aquisição de conhecimentos do estudante. Ao disponibilizar para cada estudante uma sugestão de seqüência instrucional adequada ao seu perfil atual e atualizada dinamicamente, o ambiente criará condições para que os mesmos possam guiar o próprio aprendizado de forma personalizada.Most of Learning Management Systems predominantly in use at computational support education are static and linear. They present the same instructional content for several students without considering their own knowledge acquisition level, becoming these environments sometimes unstimulating for students who are in a higher level and in other hand inhibited for students who are still in an initial level. This article aims to present the model of a computational learning environment based on the students’ knowledge acquisition level. Providing to each student a suggestion of an instructional sequence suitable to their current profile, and dynamically updated, the environment will create conditions for students guide their own learning in a personalized way.VI Workshop de Tecnología Informática Aplicada en EducaciónRed de Universidades con Carreras en Informática (RedUNCI

    A caminho de um ambiente adaptativo de aprendizagem baseado no nível de aquisição de conhecimentos do estudante

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    A grande maioria dos Sistemas de Gerenciamento de Aprendizagem predominantemente em uso no ensino com suporte computacional são estáticos e lineares, ou seja, apresentam o mesmo conteúdo instrucional para os diversos estudantes sem considerar o nível de aquisição de conhecimentos de cada um. Isso torna esses ambientes muitas vezes desestimulantes para estudantes que estão num nível mais avançado e inibidores para aqueles que estão num nível ainda inicial. Este artigo tem por objetivo apresentar o modelo de funcionamento de um ambiente computacional de aprendizagem baseado no nível de aquisição de conhecimentos do estudante. Ao disponibilizar para cada estudante uma sugestão de seqüência instrucional adequada ao seu perfil atual e atualizada dinamicamente, o ambiente criará condições para que os mesmos possam guiar o próprio aprendizado de forma personalizada.Most of Learning Management Systems predominantly in use at computational support education are static and linear. They present the same instructional content for several students without considering their own knowledge acquisition level, becoming these environments sometimes unstimulating for students who are in a higher level and in other hand inhibited for students who are still in an initial level. This article aims to present the model of a computational learning environment based on the students’ knowledge acquisition level. Providing to each student a suggestion of an instructional sequence suitable to their current profile, and dynamically updated, the environment will create conditions for students guide their own learning in a personalized way.VI Workshop de Tecnología Informática Aplicada en EducaciónRed de Universidades con Carreras en Informática (RedUNCI

    Finite-Temperature Transport in Finite-Size Hubbard Rings in the Strong-Coupling Limit

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    We study the current, the curvature of levels, and the finite temperature charge stiffness, D(T,L), in the strongly correlated limit, U>>t, for Hubbard rings of L sites, with U the on-site Coulomb repulsion and t the hopping integral. Our study is done for finite-size systems and any band filling. Up to order t we derive our results following two independent approaches, namely, using the solution provided by the Bethe ansatz and the solution provided by an algebraic method, where the electronic operators are represented in a slave-fermion picture. We find that, in the U=\infty case, the finite-temperature charge stiffness is finite for electronic densities, n, smaller than one. These results are essencially those of spinless fermions in a lattice of size L, apart from small corrections coming from a statistical flux, due to the spin degrees of freedom. Up to order t, the Mott-Hubbard gap is \Delta_{MH}=U-4t, and we find that D(T) is finite for n<1, but is zero at half-filling. This result comes from the effective flux felt by the holon excitations, which, due to the presence of doubly occupied sites, is renormalized to \Phi^{eff}=\phi(N_h-N_d)/(N_d+N_h), and which is zero at half-filling, with N_d and N_h being the number of doubly occupied and empty lattice sites, respectively. Further, for half-filling, the current transported by any eigenstate of the system is zero and, therefore, D(T) is also zero.Comment: 15 pages and 6 figures; accepted for PR

    Metabolite Profiles of Sugarcane Culm Reveal the Relationship Among Metabolism and Axillary Bud Outgrowth in Genetically Related Sugarcane Commercial Cultivars

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    Metabolic composition is known to exert influence on several important agronomic traits, and metabolomics, which represents the chemical composition in a cell, has long been recognized as a powerful tool for bridging phenotype–genotype interactions. In this work, sixteen truly representative sugarcane Brazilian varieties were selected to explore the metabolic networks in buds and culms, the tissues involved in the vegetative propagation of this species. Due to the fact that bud sprouting is a key trait determining crop establishment in the field, the sprouting potential among the genotypes was evaluated. The use of partial least square discriminant analysis indicated only mild differences on bud outgrowth potential under controlled environmental conditions. However, primary metabolite profiling provided information on the variability of metabolic features even under a narrow genetic background, typical for modern sugarcane cultivars. Metabolite–metabolite correlations within and between tissues revealed more complex patterns for culms in relation to buds, and enabled the recognition of key metabolites (e.g., sucrose, putrescine, glutamate, serine, and myo-inositol) affecting sprouting ability. Finally, those results were associated with the genetic background of each cultivar, showing that metabolites can be potentially used as indicators for the genetic background

    Cervical disc herniation and cervical spondylosis surgically treated by Cloward procedure: a 10-year-minimum follow-up study

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    BACKGROUND: Cervical degenerative pathology produces pain and disability, and if conservative treatment fails, surgery is indicated. The aim of this study was to determined whether anterior decompression and interbody fusion according to Cloward is effective for treating segmental cervical degenerative pathology and whether the results are durable after a 10-year-minimum follow-up. MATERIALS AND METHODS: Fifty-one patients affected by single-level cervical degenerative pathology between C4 and C7 were surgically treated by the Cloward procedure. Clinical evaluation was rated using the Neck Disability Index (NDI) and the visual analog scale (VAS). At last follow-up, the outcomes were rated according to Odom's criteria. On radiographs, the sagittal segmental alignment (SSA) of the affected level and the sagittal alignment of the cervical spine (SACS) were measured. RESULTS: Average NDI was 34 preoperatively and 11 at last follow-up. Average VAS was 7 preoperatively and 1 at last follow-up. According to Odom's criteria, the outcome was considered excellent in 18 cases, good in 22, and fair in 11. Average SSA was 0.5 +/- 2.1 preoperatively, 1.8 +/- 3.8 at 6 months, and 1.8 +/- 5.7 at last follow-up. Average SACS was 16.5 +/- 4.0 preoperatively, 20.9 +/- 5.8 at 6 months, and 19.9 +/- 6.4 at last follow-up. Degenerative changes at the adjacent levels were observed in 18 patients (35.3%). CONCLUSIONS: The Cloward procedure proved to be a suitable and effective technique for treating segmental cervical degenerative pathology, allowing good clinical and radiographic outcomes even at a long-term follow-up

    Ticks (Acari: Ixodidae) associated with small terrestrial mammals in the state of Minas Gerais, southeastern Brazil

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    From June 2005 to November 2010, 43 small mammals encompassing 6 species of Didelphimorphia, 8 species of Rodentia, and 1 species of Lagomorpha were found parasitized by ticks in the state of Minas Gerais, southeastern Brazil. Nine tick species, in total 186 specimens, were identified as follows: Amblyomma cajennense (larvae and nymphs) on opossums and rodents; Amblyomma ovale (nymphs) on rodents; Amblyomma parvum (nymphs) on rodents; Amblyomma coelebs (nymphs) on opossums; Amblyomma dubitatum (nymph) on opossums; Ixodes amarali (females, nymphs, and larvae) on opossums and rodents; Ixodes loricatus (male, females, nymph) on opossums; Ixodes schulzei (female) on rodents; and Haemaphysalis leporispalustris (female) on rabbits. Most of the tick-host associations found in the present study have never been recorded in the literature; those include three new host records for I. amarali, four for A. cajennense, one for A. dubitatum, two for A. ovale, and one for A. coelebs. In addition, we provide the first record of A. coelebs in the state of Minas Gerais.CNPq (Brazil)FAPESP (Brazil)INTA (Argentina)CONICET (Argentina)Asociacion Cooperadora de la EEA-INTA Rafaela (Argentina

    Diagnostic accuracy of a noninvasive hepatic ultrasound score for non-alcoholic fatty liver disease (NAFLD) in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

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    CONTEXT AND OBJECTIVE: Noninvasive strategies for evaluating non-alcoholic fatty liver disease (NAFLD) have been investigated over the last few decades. Our aim was to evaluate the diagnostic accuracy of a new hepatic ultrasound score for NAFLD in the ELSA-Brasil study.DESIGN AND SETTINGS: Diagnostic accuracy study conducted in the ELSA center, in the hospital of a public university.METHODS: Among the 15,105 participants of the ELSA study who were evaluated for NAFLD, 195 individuals were included in this sub-study. Hepatic ultrasound was performed (deep beam attenuation, hepatorenal index and anteroposterior diameter of the right hepatic lobe) and compared with the hepatic steatosis findings from 64-channel high-resolution computed tomography (CT). We also evaluated two clinical indices relating to NAFLD: the fatty liver index (FLI) and the hepatic steatosis index (HSI).RESULTS: Among the 195 participants, the NAFLD frequency was 34.4%. High body mass index, high waist circumference, diabetes and hypertriglyceridemia were associated with high hepatic attenuation and large anteroposterior diameter of the right hepatic lobe, but not with the hepatorenal index. The hepatic ultrasound score, based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe, presented the best performance for NAFLD screening at the cutoff point &#8805; 1 point; sensitivity: 85.1%; specificity: 73.4%; accuracy: 79.3%; and area under the curve (AUC 0.85; 95% confidence interval, CI: 0.78-0.91)]. FLI and HSI presented lower performance (AUC 0.76; 95% CI: 0.69-0.83) than CT.CONCLUSION: The hepatic ultrasound score based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe has good reproducibility and accuracy for NAFLD screening
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