Attitude and emotions of young Portuguese tourists toward international risk destinations.

The main goals of this ongoing study are to learn about attitude of young Portuguese tourists about risk destinations and their emotions about traveling out of the country.info:eu-repo/semantics/acceptedVersio

Configuration of self-organizing informality: socio-spatial dynamic in favelas

This paper aims to discuss on spatial patterns found in favelas throughout di erent cities worldwide, as they seem to reproduce similar con gurations and urban dynamics despite its diverse local contexts. The purpose is to explore these patterns in order to understand its social behaviour and address urban informality issues through it. To see how resilience seems to be inherent to such spaces, that grow vibrant, complex and dynamic global structures emerging and self-organizing from segregation in city space. It pursues the acknowledgement of structural morphological patterns of informality production, those genotypic characteristics that seem to be independent on culture, and might be representative of these social patterns commonly observed worldwide. Favela is observed in this study as a complex, self-organized entity, whose contrast to o cial city relies on its “bottom up” structure. It tends to follow natural rules of organization instead of formal urban strategies. Space Syntax (Hillier and Hanson, 1984) is the theoretical and methodological approach applied, through which it is possible to investigate these peculiar spatial patterns in favela, comparing several cases in Latin America, Africa and Asia. The analyses are based on axial and segment maps. Investigated variables are connectivity, local and global integration, mean depth, synergy, intelligibility, angular Choice, number and length of axes, and number and length of segments, compactness, normalized angular integration and choice for segment comparison. Findings show favela as an entity that maximises use and space into strong fragmented spatial structures, which provides the labyrinthic perception of users, but also accentuates spatial hierarchy. Topography is critical to the understanding of favela’s performance. The more accentuated, the more fragmented, labyrinthic and endogenous. Nevertheless, most analysed favelas locate in at areas and, therefore, present a tendency to better articulate with the surroundings, resulting in a softer in- and-out transition. Such topological performance seems better than Brazilian cities (Medeiros, 2013), which points out favela’s organizing structure as a possible model that could be adopted to re ne the con gurational performance of cities

Linear Theory of Electron-Plasma Waves at Arbitrary Collisionality

The dynamics of electron-plasma waves are described at arbitrary collisionality by considering the full Coulomb collision operator. The description is based on a Hermite-Laguerre decomposition of the velocity dependence of the electron distribution function. The damping rate, frequency, and eigenmode spectrum of electron-plasma waves are found as functions of the collision frequency and wavelength. A comparison is made between the collisionless Landau damping limit, the Lenard-Bernstein and Dougherty collision operators, and the electron-ion collision operator, finding large deviations in the damping rates and eigenmode spectra. A purely damped entropy mode, characteristic of a plasma where pitch-angle scattering effects are dominant with respect to collisionless effects, is shown to emerge numerically, and its dispersion relation is analytically derived. It is shown that such a mode is absent when simplified collision operators are used, and that like-particle collisions strongly influence the damping rate of the entropy mode.Comment: 23 pages, 10 figures, accepted for publication on Journal of Plasma Physic

Dificuldades na Aprendizagem da Matemática: um Estudo Com Alunos do ensino Médio

O principal objetivo desta dissertação é investigar o fenômeno da dificuldade que muitos alunos do Ensino Médio apresentam na aprendizagem da Matemática. Para tanto opta por entender a opinião desses sujeitos acerca do problema. Discute um pouco sobre a influência que a motivação pode exercer na aprendizagem. Também discorre sobre a resolução de problemas e sobre a importância que essa metodologia pode alcançar durante o processo de ensino-aprendizagem dos alunos. Optando pela pesquisa qualitativa se vale do questionário como método de recolha de informações. Aponta que os alunos entendem que o problema não está apenas no método de ensino empregado pelo professor ou na natureza abstrata da própria Matemática. Dessa forma muitos dos sujeitos que contribuíram com a pesquisa apontam a falta de base em Matemática no Ensino Fundamental e a necessidade de decorar muitas fórmulas e regras como os principais motivos para a dificuldade dos alunos para aprender a Matemática na escola. Como sugestões os alunos que preencheram os questionários apontam principalmente para a necessidade do professor mudar o método de ensino, bem como a utilização de outros recursos e/ou de exploração de situações da vida cotidiana. Propõe que é necessária a realização de novos estudos não apenas no Ensino Médio para compreender melhor o problema, mas também no Ensino Fundamental

Some reasons to build a new laser Doppler flowmeter to monitor microvascular blood flow

Disturbance in the blood microcirculation is a frequent complication in a number of common diseases including diabetes, arteriosclerosis and Raynaud’s phenomenon. In order to effectively diagnose these diseases, clinical tools able to monitor non-invasively the microvascular perfusion are required. For that purpose several techniques have been proposed. Among them, laser Doppler flowmetry (LDF) has been developed over the years, from experimental tools into commercial products, and several thousands of publications cite its use in the scientific literature. Nowadays, the LDF technique is commonly proposed in diverse applications. However, the dependence of the LDF signal on the microvascular architecture is still not known. A scientific understanding and knowledge of the LDF signal origin is not yet accessible to clinicians. Some studies proposed the use of different fiber separations or several wavelengths in order to modify the sampling depth of the LDF technique. However, further work is required to have knowledge and control over the mean sampling depth (and hence volume) in skin tissue

In Vitro Methods for Specific IgE Detection on Cow’s Milk Allergy

Background: A new method for determining serum specific IgE (IMMULITE“ 2000 3gAllergy) has recently become available. Objective: To evaluate the clinical performance of IMMULITE 2000 in the diagnosis of cow’s milk allergy compared with that of UniCAP“. Additionally, we verified the behavior of both methods at two diagnostic decision points proposed by other authors. Methods: The study population consisted of 31 children with cow’s milk allergy (group A) and a control group of 19 atopic children without food allergy(group B). A blood sample from each child was tested using both methods and the results were compared. Results: In group A, the values for cow’s milk IgE ranged from 0.35 kU/L (the lowest common detection limit) to above 100 kU/L. In group B, the values were less than 1.1 kU/L for IMMULITE 2000 and less than 1.6 kU/L for UniCAP. An agreement of 90 % in IgE classes was obtained. Both methods demonstrated exactly the same diagnostic performance(sensitivity: 100 %; specificity: 78.9 %; negative predictive value: 100%; positive predictive value: 84.6%;efficiency: 90.2 %). The evaluation of the two methods at the two different decision points proposed in the literature showed a better positive predictive value with UniCAP, but we obtained equivalent performance with IMMULITE 2000 by choosing higher cutoff values. Conclusions: We conclude that IMMULITE 2000 is as effective as UniCAP in the diagnosis of cow’s milk allergy. Both methods can be used to obtain site-specific decision points that are population, age and disease dependent

Viral Respiratory Infections in Children

Introdução: Os vírus respiratórios são uma importante causa de morbilidade e constituem a principal causa de dificuldade respiratória na infância. Os agentes mais frequentes são o vírus sincicial respiratório (VSR) e rínovirus humano (RV). Outras agentes menos comuns incluem os vírus influenza, parainfluenza, adenovírus e os mais recentemente identificados coronavírus, metapneumovírus humano e bocavírus humano. O objectivo foi descrever as infecções por vírus respiratórios numa amostra de crianças internadas. Métodos: Foi feita uma revisão dos pedidos de pesquisa de vírus respiratório em crianças abaixo dos 5 anos, internadas por infecção respiratória entre 1 de Outubro de 2010 e 15 de Fevereiro de 2012 e dos respectivos processos clínicos. Resultados: Foi realizada pesquisa de vírus respiratórios por imunoflorescência directa em 664 crianças, com resultados positivos em 268 (40.4%): VSR (n=240, 89.6%), metapneumovírus (n=10), influenza A (n=7), parainfluenza (n=6), adenovírus (n=2) e 3 casos de co-infecção. O maior número de casos positivos ocorreu entre Dezembro 2010 e Janeiro 2011 (n=263, 39.6% do total de casos positivos) e Dezembro 2011 e Janeiro 2012 (n=183, 27.6% do total de casos positivos). A maioria das crianças apresentava infecções adquiridas na comunidade (n=605, 91.1%), com dificuldade respiratória em 422 casos (69.8%). Os restantes casos correspondiam a infecções nosocomiais (n=59, 8.9%). A infecção por VSR foi mais frequente em crianças abaixo dos seis meses (65.2%, p<0.0001) e associou-se de forma estatisticamente significativa a dificuldade respiratória (96.3%, p<0.0001), hipoxémia e corticoterapia sistémica (35.6%, p=0.0001). A maioria das crianças com sibilância recorrente apresentava dificuldade respiratória (91.9%, p<0.0001). Discussão: Nas infecções respiratórias na infância com necessidade de internamento destaca-se a preponderância de infecções por VSR, com padrão sazonal típico (com pico de incidência nos meses de Inverno) e o maior risco de internamento em infecções por VSR abaixo dos 6 meses de idade

ARPES Study of the Metal-Insulator Transition in Bismuth Cobaltates

We present an angle-resolved photoemission spectroscopy (ARPES) study of a Mott-Hubbard-type bismuth cobaltate system across a metal-insulator transition. By varying the amount of Pb substitution, and by doping with Sr or Ba cation, a range of insulating to metallic properties is obtained. We observe a systematic change in the spectral weight of the coherent and incoherent parts, accompanied by an energy shift of the incoherent part. The band dispersion also shows the emergence of a weakly dispersing state at the Fermi energy with increasing conductivity. These changes correspond with the changes in the temperature-dependent resistivity behavior. We address the nature of the coherent-incoherent parts in relation to the peak-dip-hump feature seen in cuprates superconductors