Dynamics of a backlash chain

This paper studies the dynamical properties of a system with distributed backlash and impact phenomena. This means that it is considered a chain of masses that interact with each other solely by means of backlash and impact phenomena. It is observed the emergence of non-linear phenomena resembling those encountered in the Fermi-Pasta-Ulam problem.

A relevância e utilidade das demonstrações financeiras : a perceção dos gestores das PME

Mestrado em Contabilidade e Gestão das Instituições Financeiras

Desafios e potencialidades da metodologia SROI : um estudo de caso

Mestrado em Controlo e Gestão dos Negócios

Miocene catfishes (Ariidae,Bagridae) from Lisbon: a Nilotic (or Sudanian) type fauna

Miocene catfishes from Lisbon are dealt with. Two distinct sets of pectoral and dorsal pterygiophores are described. That from the Langhian V-b is referred to Arius sp. probably close to A. heudeloti. Another ser from the uppermost Burdigalian V-a may be ascribed to a bagrid, cf. Chrysichthys sp., identified for the first time in this region. The catfish and Lates association is sctrikingly similar to African, nilotic or sudanian ones as far as freshwaters are concerned. In marine, coastal environments, stenotherm warm-water forms (Polynemids, large barracudas and several sharks) indicate, as a model, faunas like chose from Cape Verde to northern Angola. There is some gradation for brackish waters (fig. 1). Catfishes and Lates probably migrated into the Iberian Peninsule in the lower Miocene. They are unknown after Langhian V-b except for a reappearance of Arius in the middle Tortonian VII-b. Decreasing temperatures and aridity account for local extinction at least in freshwaters. Expansion of these fishes have been made easier owing to the displacement of land masses chat narrowed or closed the marine waterway between Europe and Africa. Salinity tolerance is not necessarily the sole explanation for migration. Catfishes plus Lates associations colonized inland waters from both sides of the Paleomediterranean. Local extinction may have weighed more in the development of modern distribution patterns than migration.

Factors associated with arterial stiffness in children aged 9-10 years

OBJECTIVE To analyze the factors associated with stiffness of the great arteries in prepubertal children.METHODS This study with convenience sample of 231 schoolchildren aged 9-10 years enrolled in public and private schools in Vitória, ES, Southeastern Brazil, in 2010-2011. Anthropometric and hemodynamic data, blood pressure, and pulse wave velocity in the carotid-femoral segment were obtained. Data on current and previous health conditions were obtained by questionnaire and notes on the child’s health card. Multiple linear regression was applied to identify the partial and total contribution of the factors in determining the pulse wave velocity values.RESULTS Among the students, 50.2% were female and 55.4% were 10 years old. Among those classified in the last tertile of pulse wave velocity, 60.0% were overweight, with higher mean blood pressure, waist circumference, and waist-to-height ratio. Birth weight was not associated with pulse wave velocity. After multiple linear regression analysis, body mass index (BMI) and diastolic blood pressure remained in the model.CONCLUSIONS BMI was the most important factor in determining arterial stiffness in children aged 9-10 years.

Geodynamics of the eastern sector of the Arrábida chain (W Portugal)

N.º4, p.263-267

Abelian realization of phenomenological two-zero neutrino textures

In an attempt at explaining the observed neutrino mass-squared differences and leptonic mixing, lepton mass matrices with zero textures have been widely studied. In the weak basis where the charged lepton mass matrix is diagonal, various neutrino mass matrices with two zeros have been shown to be consistent with the current experimental data. Using the canonical and Smith normal form methods, we construct the minimal Abelian symmetry realizations of these phenomenological two-zero neutrino textures. The implementation of these symmetries in the context of the seesaw mechanism for Majorana neutrino masses is also discussed. (C) 2014 The Authors. Published by Elsevier B.V.

Constraining multi-Higgs flavour models

To study a flavour model with a non-minimal Higgs sector one must first define the symmetries of the fields; then identify what types of vacua exist and how they may break the symmetries; and finally determine whether the remnant symmetries are compatible with the experimental data. Here we address all these issues in the context of flavour models with any number of Higgs doublets. We stress the importance of analysing the Higgs vacuum expectation values that are pseudo-invariant under the generators of all subgroups. It is shown that the only way of obtaining a physical CKM mixing matrix and, simultaneously, non-degenerate and non-zero quark masses is requiring the vacuum expectation values of the Higgs fields to break completely the full flavour group, except possibly for some symmetry belonging to baryon number. The application of this technique to some illustrative examples, such as the flavour groups Delta (27), A(4) and S-3, is also presented.

Severity of malocclusion in adolescents: populational-based study in the north of Minas Gerais, Brazil

ABSTRACT OBJECTIVE To identify the factors associated with severity of malocclusion in a population of adolescents. METHODS In this cross-sectional population-based study, the sample size (n = 761) was calculated considering a prevalence of malocclusion of 50.0%, with a 95% confidence level and a 5.0% precision level. The study adopted correction for the effect of delineation (deff = 2), and a 20.0% increase to offset losses and refusals. Multistage probability cluster sampling was adopted. Trained and calibrated professionals performed the intraoral examinations and interviews in households. The dependent variable (severity of malocclusion) was assessed using the Dental Aesthetic Index (DAI). The independent variables were grouped into five blocks: demographic characteristics, socioeconomic condition, use of dental services, health-related behavior and oral health subjective conditions. The ordinal logistic regression model was used to identify the factors associated with severity of malocclusion. RESULTS We interviewed and examined 736 adolescents (91.5% response rate), 69.9% of whom showed no abnormalities or slight malocclusion. Defined malocclusion was observed in 17.8% of the adolescents, being severe or very severe in 12.6%, with pressing or essential need of orthodontic treatment. The probabilities of greater severity of malocclusion were higher among adolescents who self-reported as black, indigenous, pardo or yellow, with lower per capita income, having harmful oral habits, negative perception of their appearance and perception of social relationship affected by oral health. CONCLUSIONS Severe or very severe malocclusion was more prevalent among socially disadvantaged adolescents, with reported harmful habits and perception of compromised esthetics and social relationships. Given that malocclusion can interfere with the self-esteem of adolescents, it is essential to improve public policy for the inclusion of orthodontic treatment among health care provided to this segment of the population, particularly among those of lower socioeconomic status.

INbreast: Toward a Full-field Digital Mammographic Database

Rationale and Objectives Computer-aided detection and diagnosis (CAD) systems have been developed in the past two decades to assist radiologists in the detection and diagnosis of lesions seen on breast imaging exams, thus providing a second opinion. Mammographic databases play an important role in the development of algorithms aiming at the detection and diagnosis of mammary lesions. However, available databases often do not take into consideration all the requirements needed for research and study purposes. This article aims to present and detail a new mammographic database. Materials and Methods Images were acquired at a breast center located in a university hospital (Centro Hospitalar de S. João [CHSJ], Breast Centre, Porto) with the permission of the Portuguese National Committee of Data Protection and Hospital's Ethics Committee. MammoNovation Siemens full-field digital mammography, with a solid-state detector of amorphous selenium was used. Results The new database—INbreast—has a total of 115 cases (410 images) from which 90 cases are from women with both breasts affected (four images per case) and 25 cases are from mastectomy patients (two images per case). Several types of lesions (masses, calcifications, asymmetries, and distortions) were included. Accurate contours made by specialists are also provided in XML format. Conclusion The strengths of the actually presented database—INbreast—relies on the fact that it was built with full-field digital mammograms (in opposition to digitized mammograms), it presents a wide variability of cases, and is made publicly available together with precise annotations. We believe that this database can be a reference for future works centered or related to breast cancer imaging.

ERICA: use of screens and consumption of meals and snacks by Brazilian adolescents

ABSTRACT OBJECTIVE To describe the length of exposure to screens and the prevalence of consumption of meals and snacks by Brazilian adolescents in front of screens. METHODS We evaluated 74,589 12 to 17-year old adolescents from 1,247 schools in 124 Brazilian municipalities. A self-administered questionnaire was used. Its segment regarding nutrition contained questions about using TV, computers, and video game systems, having meals while watching TV, and consuming snacks in front of screens. Consumption of meals and snacks in front of screens was analyzed according to the following variables: geographical region, gender, age range, type of school (public or private), and school shift. The prevalences and their respective 95% confidence intervals were estimated under a complex sampling design. RESULTS A great deal of the adolescents (73.5%, 95%CI 72.3-74.7) reported spending two or more hours a day in front of screens. That habit was more frequent among male adolescents, private school students, morning shift students, and students from Brazil’s South region. More than half of the adolescents (56.6%, 95%CI 55.4-57.8) reported almost always or always having meals in front of TV, and 39.6% (95%CI 38.8-40.5) of them said they consumed snacks in front of screens exactly as often. Both situations were the most prevalent ones among the girls, who attended public schools and were from Brazil’s Midwest region. CONCLUSIONS Length of exposure to screens and consumption of meals and snacks almost always or always in front of screens are high among Brazilian adolescents. It is necessary to develop strategies aiming to reduce the length of screen use, considering the media reality that children and adolescents have been experiencing from earlier and earlier ages. That context must therefore be analyzed in an indissociable way.

Design and construction of tunnels in zones subjected to high convergences

The economic development of a region depends on the speed that people and goods can travel. The reduction of people and goods travel time can be achieved by planning smooth road layouts, which are obtained by crossing natural obstacles such as hills, by tunneling at great depths, and allowing the reduction of the road alignment length. The stress state in rock masses at such depths, either because of the overburden or due to the tectonic conditions of the rock mass induces high convergences of the tunnel walls. These high convergence values are incompatible with the supports structural performance installed in the excavation stabilization. In this article it is intended to evaluate and analyze some of the solutions already implemented in several similar geological and geotechnical situations, in order to establish a methodological principle for the design of the tunnels included in a highway section under construction in the region influenced by the Himalayas, in the state of Himachal Pradesh (India) and referenced by "four laning of Kiratpur to Ner Chowk section".

Desenvolvimento de ferramentas e provetes para o ensaio Thick Adherend Shear Test (TAST).

As estruturas coladas são geralmente projetadas para que o adesivo seja essencialmente sujeito a esforços de corte, pois neste tipo de solicitação o adesivo apresenta melhores caraterísticas mecânicas. A avaliação do comportamento ao corte pode ser realizada com o adesivo no estado maciço ou como camada fina em juntas adesivas. Os métodos que permitem avaliar o comportamento ao corte, quer para o adesivo, quer para as juntas, são: o ensaio Iosipescu ou V-Notched beam shear method, o ensaio de borboleta ou Notched plate shear method (Arcan), o ensaio de torsão, o ensaio de tração numa junta de sobreposição simples e o ensaio Thick Adherend Shear Test (TAST). Os ensaios Arcan e Iosipescu, tal como o ensaio de torção, podem ser realizados em provetes de adesivo maciço ou em juntas. O ensaio de torção é pouco utilizado, porque a aplicação do esforço de corte exige dispositivos e equipamentos de ensaios complexos. Os ensaios Arcan e Iosipescu utilizam provetes com entalhes e podem introduzir alguma dificuldade na medição precisa das deformações. O ensaio de tração numa junta de sobreposição simples é um dos métodos mais usados para caraterizar uma junta adesiva, porque é um método simples, as juntas são de fácil fabrico e pode ser realizado em máquinas universais de ensaios mecânicos. Neste ensaio os aderentes estão sujeitos a uma solicitação de tração, enquanto a camada de adesivo está sujeita a esforços de corte combinados com esforços de arrancamento. Os esforços de arrancamento resultam da própria geometria da junta na qual existe um desalinhamento das forças de tração, mesmo quando são colocados calços (reguladores de espessura) nos locais de amarração. O ensaio TAST é dos mais populares para obtenção das propriedades ao corte, uma vez que tanto as ferramentas de ensaio como o fabrico dos provetes são relativamente simples. Este ensaio é realizado em junta sendo os substratos espessos e de aço que, devido à sua elevada rigidez, contribuem para um esforço de corte praticamente puro no adesivo. Neste trabalho realizou-se o projeto e a fabricação das ferramentas, gabarit e substratos necessários para a execução de provetes TAST e ensaios utilizando diferentes adesivos.

Integração de um sistema de gestão de informação clínica hospitalar numa unidade de cuidados continuados

O crescimento da população idosa impõe o desenvolvimento de serviços de qualidade orientados para as necessidades comuns desta faixa etária. A área dos cuidados continuados corresponde a um segmento em crescimento com um forte potencial de desenvolvimento no que concerne ao domínio dos sistemas de informação (SI). O presente trabalho pressupõe o acompanhamento do processo de integração de um SI de uma Unidade Hospitalar (UH) numa Unidade de Cuidados Continuados (UCC) para idosos. A análise envolveu o recurso à Teoria Actor-network (ANT), enquanto posicionamento teórico de relevo para o desenvolvimento de SI. Esta teoria coloca, equitativamente, em destaque os factores humano e não humano como concorrentes para o sucesso no desenvolvimento de um SI. O processo em destaque neste trabalho envolveu a análise compreensiva dos SI das unidades de saúde envolvidas; monitorização e descrição do processo de integração do SI de inspiração hospitalar na UCC; avaliação do resultado final; estabelecimento de requisitos fundamentais para o desenho de um SI adaptado a uma organização prestadora de cuidados continuados a idosos. Estas etapas foram desenvolvidas tendo por base a concretização de 3 ciclos, integradores dos conceitos da ANT com o processo de Engenharia de Requisitos: Ciclo 1 - análise do sistema sócio-técnico; Ciclo 2 – desenho do novo sistema sócio-técnico; Ciclo 3 – transformação da rede sócio-técnica. A metodologia inerente ao processo envolveu a análise documental, realização de notas de campo, entrevista e questionário. Os requisitos são apresentados através da conceptualização de um SI denominado Gestão de Cuidados Residenciais (GCR). Conclui-se, que para que um SI resulte com eficácia, eficiência e efetividade para uma organização, deverá revelar-se adaptado ao propósito e missão da organização em causa, sob pena de induzir fragilidade ao ciclo operacional e ao modelo de gestão de informação.

Influência dos parâmetros geotécnicos na qualidade do desmonte de maciços rochosos fracturados

Uma das operações envolvidas no desmonte de maciços rochosos é a perfuração. A forma como esta é executada é determinante para o sucesso do desmonte. Quando realizada correctamente o desmonte produz uma boa fragmentação, reduzindo a sobrescavação. Assim, a correcta escolha das ferramentas de perfuração assume um papel preponderante para os custos do desmonte em maciço rochosos. Esta dissertação irá centrar-se nos parâmetros Geológicos, Geotécnicos e Geomecânicos e nos desvios de perfuração. O objectivo geral deste trabalho é perceber a interdependência dos parâmetros geológicogeotécnicos e geomecânicos do maciço rochoso com os desvios de perfuração, bem como estudar os ângulos de intersecção entre os furos e as descontinuidades que originam o desvio. O estudo dos parâmetros do maciço rochoso aliado a uma perfuração alinhada é salientado com o intuito de uma abordagem de geoengenharia integrada dos maciços rochosos.