585 research outputs found
Hypothetical answers to continuous queries over data streams
Continuous queries over data streams may suffer from blocking operations
and/or unbound wait, which may delay answers until some relevant input arrives
through the data stream. These delays may turn answers, when they arrive,
obsolete to users who sometimes have to make decisions with no help whatsoever.
Therefore, it can be useful to provide hypothetical answers - "given the
current information, it is possible that X will become true at time t" -
instead of no information at all.
In this paper we present a semantics for queries and corresponding answers
that covers such hypothetical answers, together with an online algorithm for
updating the set of facts that are consistent with the currently available
information
GeoGebra e ferramentas tradicionais: uma conjugação favorável à apropriação das isometrias
O presente artigo propõe-se divulgar parte de uma investigação que perseguiu como uma das principais finalidades analisar o potencial da exploração do GeoGebra, complementada com ferramentas tradicionais, no desenvolvimento de competências geométricas, relacionadas com as isometrias e os frisos, em alunos do 1.º ciclo do ensino básico. No âmbito do trabalho empírico, desenvolveu-se um estudo de caso múltiplo centrado em dois pares de alunos do 4.º ano de escolaridade que resolveram autonomamente, por recurso àquelas tecnologias, uma bateria de tarefas de natureza essencialmente exploratória. Os dados foram recolhidos através das técnicas de inquirição, observação direta e participante e análise documental. A análise de conteúdo a que foram submetidos permitiu concluir que uma abordagem didática centrada em sequências de tarefas a resolver com recurso a tecnologias tradicionais conjugadas com o GeoGebra potencia uma apropriação mais sólida dos conceitos geométricos em causa e sua aplicação. Além disso, contribuiu ainda para o desenvolvimento de atitudes favoráveis em relação à matemática e à geometria, em particular.This article intends to disseminate part of an investigation that aims to analyze the potential of GeoGebra, complemented with traditional tools, in the development of geometric competences related to isometries and the friezes, in elementary school. Within the empirical work, we developed a case study focused on two pairs of students in the 4th grade who solved autonomously, using those technologies, a battery of exploratory tasks. The data was collected mainly through inquiry techniques, direct observation and documentary analysis. Its content analysis allowed us to conclude that the didactical approach, centered on sequences of tasks to be solved using traditional technologies combined with GeoGebra, enhances a more solid appropriation of the focused geometric concepts and its application. Moreover, it has also contributed to the development of positive attitudes towards Mathematics and particularly to Geometry
Proteomic analysis of the human vitreous humor in Retinal Detachment
Over the past few years, there has been an intensification in onset of ocular diseases among worldwide population. The incidence of eye pathologies upsurges with advancing age, leading to a decline of normal eye function and even to blindness. Ocular diseases are frequently triggered by chronic disorders, such as diabetes or hypertension, or by alterations in retinal positioning, which occurs in retinal detachment (RD). Recent studies indicates that human vitreous humor (VH) suffers proteome alterations according to the actual physiological and pathological state of the retina. However, there are few published articles regarding RD proteome. Hence, this study is focused in the proteomic analysis of VH samples in RD and posterior identification of the present proteins in these samples, as well as to understand in what way they are connected and how they act. In this way, we can get access to the VH proteome in RD patients, which is our main goal. To achieve these goals, several strategies were combined, including high abundant proteins depletion, protein fractionation and analysis by mass spectrometry (MS), in order to maximize the number of identified proteins. The final optimized strategy combined protein fractionation using liquid chromatography (LC), SDS-PAGE, and protein identification by MALDI-TOF/TOF. Using this methodology, we found 236 proteins with a 95% confidence, using ProteinPilot, where 46 proteins share common biological associations, with a minimum score of 0.900 according to STRING10. The majority of these 46 proteins are involved in regulation processes and share binding functions. Simultaneously, the same VH group sample was analyzed by LC and MALDI-TOF/TOF, in order to understand the importance of the implementation of SDS-PAGE in the process. Thus, we verified that with LC-MALDI only 110 proteins were identified. In conclusion, the developed strategy allowed to find proteins which were not identified using other proteomic strategies.Nos últimos anos, tem-se verificado um grande incremento de doenças oculares na população mundial. A incidência destas patologias surge com a progressão da idade, levando a um declínio da função ocular normal e, em alguns casos, podendo levar à cegueira. As patologias oculares são frequentemente desencadeadas por doenças crónicas, tais como diabetes ou hipertensão, ou por alterações no posicionamento da retina, o que ocorre no descolamento de retina (DR). Estudos recentes indicam que o humor vítreo (HV) humano sofre alterações proteómicas, de acordo com o estado fisiológico e patológico da retina. No entanto, existem poucos estudos publicados sobre o proteoma do HV no DR. Assim, este estudo centra-se essencialmente na análise proteómica de amostras de HV em DR, e posterior identificação das proteínas presentes nestas amostras, de que forma estão interligadas e como atuam. Desta forma, pode ter-se acesso ao proteoma do HV em doentes com descolamento de retina, que é o principal objetivo deste trabalho.
Para atingir estes objetivos, diversas estratégias foram combinadas, incluindo a depleção de proteínas abundantes, fracionamento e análise de proteínas por espectrometria de massa (MS), a fim de maximizar o número de proteínas identificadas. A estratégia final otimizada combinou o fracionamento de proteínas por cromatografia líquida (LC) e SDS-PAGE e a identificação das proteínas por MALDI-TOF/TOF. Usando esta metodologia, foram identificadas 236 proteínas com uma confiança de 95%, usando o ProteinPilot, onde 46 proteínas partilham associações biológicas comuns, com um score mínimo de 0.900 de acordo com o STRING10. A maioria dessas 46 proteínas estão envolvidas em processos de regulação e têm funções de ligação. Em simultâneo, analisou-se o mesmo grupo de amostras através de LC e MALDI-TOF/TOF, de forma a compreender a importância da implementação de SDS-PAGE no processo. Verificou-se que através de LC-MALDI, apenas 110 proteínas foram identificadas. Em conclusão, a estratégia desenvolvida (LC-SDS-MALDI) permitiu encontrar proteínas que não tinham sido anteriormente identificadas usando outras estratégias proteómicas
Being LGBT and having functional diversity: discourses and practices of portuguese professionals
Does diversity in top management teams contribute to organizational performance? The response of IBEX 35 companies
This study contributes to the spread of theoretical and empirical knowledge regarding the Upper Echelons Theory, considering the training and demographic diversity in the Top Management Team (TMT) as a singular characteristic of each company, in our case those belonging to the IBEX35 index. Taking into account the skills of the members, a greater financial performance is expected. Once we obtained the statistical results, we concluded that the inclusion of women in the TMT increased Net Sales and EBITDA. Features such as age, training and nationality are also examined in this work.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
The Portuguese Coast
SFRH/BPD/70384/2010
UID/ELT/00657/2013In Portugal the connection with the sea is very ancient — that, at least, is the idea passed down through the generations, and taken to be a source of national pride. In Portuguese traditional literature, however, the sea and maritime matters are little discussed, compared to rural affairs, which is something of a contradiction for a nation that defines itself as “essentially maritime”. The historical data, too, seem to contradict the idea of a broadly maritime vocation. This article deals with the relationship the Portuguese have with their coastline, trying to understand the forms of settlement of that space. By comparing historical sources with the texts from the popular tradition we can determine the reasons – either real (piracy, storms and shipwrecks, scarcity of resources) or imaginary (fear of the unknown) – for the scant population of long stretches of the Portuguese coastline up to the nineteenth century. The image of an uninviting, hostile and deserted coastline transmitted through the popular tradition and the historical record fits in well with that theorized by Yi-Fu Tuan, in his work, Landscapes of Fear. Broadly speaking, the topos of ancestral fears of Portuguese popular tradition correlates with Tuan’s arguments: the landscapes of fear are spaces which represent desert, wilderness, no-man’s-land. In Portugal the nineteenth century represents a turning point for the coast, because it was then that it became a space for the recreation and leisure of the elites.authorsversionpublishe
An approach to teach Calculus/Mathematical Analysis (for engineering students) using computers and active learning – its conception, development of materials and evaluation
Dissertação para obtenção do Grau de Doutor em
Ciências da EducaçãoThis thesis reports a new approach to the teaching of Mathematical Analysis 1/ Calculus (AM1) to students of engineering, applying results of research on the use of computers and active learning with the aim of enhancing understanding. The main goal of the new approach is to reduce the known problem of failure and superficial understanding in introductory college mathematics in Portugal (and other countries).
This researcher created the approach named ActivMathComp where:
- Students are active and collaborate with colleagues during classes;
- Computer is embedded as a communication, interaction and computational tool;
- Students use interactive digital learning documents;
- Students explore concepts in order to develop a deep understanding of them;
- Students contact with mathematical applications;
- Students have frequent short quizzes with immediate feedback on a Learning Management System;
- The teacher/student relationship is grounded on trust, on mutual understanding and on students’ involvement on their own learning.
The interactive digital documents were created assuming principles such as the zone of proximal development and multiple representations.
Towards its comparison with the traditional approach, the ActivMathComp was implemented in a group of 16 AM1 students at the Civil Engineering Undergraduate Program of the Instituto Superior de Engenharia de Lisboa. The participants freely chose to enrol in the group and were required to bring their own laptop to classes. Took place a quasi-experiment where all the other seven classes following AM1 were taken as a comparison group.
The participating students got significantly higher grades than the other students and had a higher success rate. Data gathered from questionnaires and tests were screened to identify possible bias. The participating students evaluated ActivMathComp as highly positive in nearly all aspects
Impact of the social support satisfaction in health-related quality of life in portuguesechildren and adolescents
Gestión Internacional de los Recursos Humanos. El caso de la expatriación-repatriación de directivos de las empresas energéticas del IBEX-35
La presente investigación pretende presentar el marco conceptual y el estado de la cuestión en lo que
a expatriación/repatriación de directivos se refiere, para continuar analizando una serie de factores a
considerar en este proceso de internacionalización de empresas y simultáneamente de recursos
humanos de las mismas.Se presenta un estudio de casos, tomando como muestra las empresas energéticas del
IBEX 35.El presente trabajo de investigación presenta, a partir de una revisión de la literatura existente, el
marco conceptual y el estado de la cuestión de la problemática de los recursos humanos en las
empresas globalizadas, haciendo especial referencia a la expatriación y repatriación de directivos.
En base a ello y a una base de datos recogidos en el periodo 2010-2015, se identifican los
principales factores a considerar en los procesos de expatriación-repatriación, y se lleva a cabo un
estudio empírico a partir del análisis de casos, tomando como muestra las empresas del petróleo y
la energía del IBEX 35. Finalmente, a partir de las conclusiones obtenidas con este estudio teóricoempírico,
se formulan una serie de propuestas para que la movilidad internacional de los recursos
humanos constituya una ventaja competitiva para las organizaciones y para el desarrollo de cada
individuoUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Qualidade de vida na demência – adaptação transcultural dos questionários DEMQOL e DEMQOL-Proxy para a população portuguesa: equivalência semântica, conceptual e de conteúdo
Objetivo - Adaptar e realizar a transculturação dos questionários DEMQOL e DEMQOL-Proxy para a população portuguesa, construídas por Smith et al, em 2005, que pretendem colmatar as lacunas existentes aos dados relacionados com a qualidade de vida no que remete a esta em utentes com demência leve, moderada e severa.
Metodologia – A metodologia inclui a parte de revisão da literatura (problemática em questão) e o processo de adaptação dos questionários. O processo implica tradução, retroversão, revisão e adaptação cultural à nossa cultura. Foram recolhidos alguns dados demográficos, com o intuito de melhor caracterização da população.
Resultados – Os questionários DEMQOL e DEMQOL_Proxy versão portuguesa demostraram muito boa consistência interna α = 0,747 e 0,812, respetivamente. Apresentam excelente reprodutibilidade entre itens (ICC= 0,845 (-0,484 – 0,984; IC 95%) para o DEMQOL e 0,812 (0,636 – 0,928; IC 95%) para o DEMQOL-Proxy.
Conclusões – Foi conseguida a equivalência semântica, conceptual e de conteúdo dos questionários que mostraram ser indicados para a população portuguesa, com bons indicadores em algumas das suas propriedades psicométricas, nomeadamente: consistência interna e reprodutibilidade entre itens
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