Procura estruturada de textos para perfis de utilizadores

A dimensão cada vez mais colossal e a falta de estruturação da informação existente na Web, está a fazer com que os sistemas de Information Retrieval enfrentem graves dificuldades no cumprimento dos objectivos para os quais foram criados. Tornase cada vez mais difícil para estes sistemas encontrarem um conjunto limitado e valioso com a informação procurada pelo utilizador. A consciência deste facto ao longo dos anos tem proporcionado um aumento da comunidade de investigadores que se debatem na exploração de diversos temas e conceitos capazes de solucionarem os problemas. Das diversas propostas, as mais promissoras são o clustering dos resultados e a personalização. O clustering permite que a informação devolvida seja organizada em categorias, dando ao utilizador a possibilidade de restringir a sua área de procura com base na escolha das categorias mais apelativas. Por sua vez, a personalização procura escolher automaticamente os resultados que são mais próximos do perfil do utilizador, efectuando uma reordenação da informação de acordo com os interesses de cada um. A comunidade científica ainda não construiu um sistema que fizesse a união das duas metodologias no que toca à personalização e necessária construção de perfis de utilizadores, com base na categorização dos resultados de pesquisas e das respectivas queries introduzidas pelos utilizadores. A criação de perfis passa geralmente pela obtenção das categorias de interesse com base na análise dos documentos lidos e classificados como relevantes para o utilizador. Estas categorias poderiam ser extraídas sem a necessidade de efectuar este tipo de análise de documentos, bastando para isso fazer uma relação entre queries e clusters dos resultados associados a essas queries. Este é o tema da proposta de trabalho apresentada nesta tese. A criação de perfis de utilizadores tendo por base a análise do histórico das pesquisas efectuadas pelos mesmos, bem como a categorização dos resultados para extrair conhecimento oculto e auxiliar a criação destes perfis. Ao serem criados perfis de utilizadores, torna-se possível para um sistema identificar o conteúdo que está mais associado aos interesses de cada pessoa, potencializando-se assim a interactividade entre o sistema e o utilizador

Experimental study on RSS based indoor positioning algorithms

This work compares the performance of indoor positioning systems suitable for low power wireless sensor networks. The research goal is to study positioning techniques that are compatible with real-time positioning in wireless sensor networks, having low-power and low complexity as requirements. Map matching, approximate positioning (weighted centroid) and exact positioning algorithms (least squares) were tested and compared in a small predefined indoor environment. We found that, for our test scenario, weighted centroid algorithms provide better results than map matching. Least squares proved to be completely unreliable when using distances obtained by the one-slope propagation model. Major improvements in the positioning error were found when body influence was removed from the test scenario. The results show that the positioning error can be improved if the body effect in received signal strength is accounted for in the algorithms.Helder D. Silva is supported by the Portuguese Foundation for Science and Technology under the grant SFRBD/78018/2011.info:eu-repo/semantics/publishedVersio

Body attenuation and path loss exponent estimation for RSS-based positioning in WSN

The influence of the human body in antenna systems has significant impact in the received signal strength (RSS) of wireless transmissions. Accounting for body effect is generally considered as being able to improve position estimation based on RSS measurements. In this work we perform several experiments with a wireless sensor network, using a sensor node equipped with an inertial measurement unit (IMU), in order to obtain the relative orientation between the sensor node and multiple anchor nodes. A model of the RSS attenuation induced by the body was created using experimental measurements in a controlled environment and applied to a real-time positioning system. A path loss exponent (PLE) estimation method using RSS information from neighbor anchors was also implemented and evaluated. Weighted centroid localization (WCL) algorithm was the positioning method used in this work. When the sensor node was placed on the user’s body, accounting for body effect produced negligible improvements (6%) in the best-case scenario and consistently degraded accuracy under real conditions, whether the node was placed on the user’s body (in the order of 3%), 10 cm away (from 14% to 35%) or 20 cm away from the body (from 42% to 105%) for results in the 70th percentile. The PLE estimation method showed improvements (in the order of 11%) when the sensor node is further away from the body. Results demonstrate that the distance between sensor node and the body has an extremely important influence on the accuracy of the position estimate.This work has been supported by FCT (Fundação para a Ciência e Tecnologia) in the scope of the project UID/EEA/04436/2013. Helder D. Silva is supported by FCT under the grant SFRH/BD/78018/2011info:eu-repo/semantics/publishedVersio

A Look at Doctoral Theses in Mathematics Education at Andalusian Universities (2010-2020) from a Gender Perspective

In recent years, bibliometric studies on mathematics education have allowed us to learn more about the scientific production in this field. To continue this line of study, in this research we have focused on the doctoral theses published on mathematics education and, in particular, on the role of women in the production, direction and evaluation of doctoral theses in this field, focusing on Andalusian universities. For this purpose, a bibliometric study has been carried out using the Teseo database. The results show a decrease in Andalusian doctoral production in this field in recent years and how, although the number of women who have completed doctoral theses in this field is greater than that of men, in the case of the direction of them, the number of male directors is greater than men directors

Creation of a 3D Animation on Evanescent Wave Microscopy and its application in Virology: a tool for the study and understanding of the mechanisms of infection by microorganisms in living cells

En el estudio de los mecanismos de invasión por patógenos (virus, bacterias, parásitos), es importante abordar, a nivel avanzado y molecular, los procesos que gobiernan la fusión de membrana, como uno de los eventos biológicos clave en la infección por microorganismos y en el contexto de las Enfermedades Infecciosas. En este contexto, es importante entender cómo funcionan las proteínas de los patógenos que regulan la invasión de células y tejidos, mediante el control y promoción del proceso de fusión de membrana entre el patógeno y la célula diana. Donde el empleo de la miscroscopía de onda evanescente es importante. Las ilustraciones científicas en este tema suelen ser láminas o esquemas 2D fijos, que ilustran la función de las proteínas implicadas y la fusión de membranas entre patógeno y célula diana, con cadenas secuenciales de imágenes no dinámicas, y difícilmente se ilustra el funcionamiento de este microscopio de última generación. En este capítulo se presenta, a modo de resumen, nuestro proyecto de innovación docente ULL, cuyo objetivo ha sido la creación y generación, por vez primera, de material de Animación 3D para ilustrar de forma pedagógica, y con el mayor reigor ciéntifico, la aplicación de la tecnología de microscopía fluorescente de onda evanescente (TIRFM) en el estudio de células vivas y del mecanismo de su infección por patógenos, aplicándolo a la comprenión del proceso de fusión de membranas y, en particular, al proceso de infección temprana por el virus VIH-1.In the study of the mechanisms of invasion by pathogens (viruses, bacteria, parasites), it is important to address, at an advanced and molecular level, the processes that govern membrane fusion, as one of the key biological events in infection by microorganisms and in the context of Infectious Diseases. In this scenario, it is important to understand how the proteins of the pathogens that regulate the invasion of cells and tissues work, by controlling and promoting the process of membrane fusion between the pathogen and the target cell. In this matter, the use of evanescent wave microscopy (TIRFM) is key and very important. The scientific illustrations in this topic are usually fixed sheets or 2D-diagrams that illustrate the function of the proteins involved and the fusion of membranes between pathogen and target cell, with sequential chains of non-dynamic images, where it is difficult to illustrate how this last generation microscope works. In this chapter we briefly present our ULL teaching innovation project, whose objective has been the creation and generation, for the first time, of a 3D Animation material to illustrate in a pedagogical way, and with the greatest scientific rigor, the application of the evanescent wave fluorescence microscopy technology in the study of living cells and the mechanism of their infection by pathogens, applying it to the understanding of the membrane fusion process and, in particular, to the process of early infection by the HIV-1

Hyperhomocyst(e)inemia in chronic stable renal transplant patients

OBJETIVOS: A hiper-homocisteinemia é um fator de risco importante para aterosclerose e, esta é uma das principais causas de óbito em transplantados renais. O objetivo deste estudo é avaliar a influência da terapêutica imunossupressora na homocisteinemia de receptores de transplante renal. CASUÍSTICA E MÉTODO: Vinte e nove pacientes foram divididos em dois grupos: grupo I (n=20) - pacientes transplantados renais em uso de ciclosporina, azatioprina e prednisona; grupo II (n=9) - pacientes transplantados renais em uso de azatioprina e prednisona; grupo III (n=7) doadores de rim para pacientes dos grupos I e II, constituíram o grupo controle. O nível sérico de creatinina e o clearance estimado de creatinina, o nível sérico de ciclosporina, o perfil de lipídeos, a concentração de ácido fólico e vitamina B12 e as características clínicas dos indivíduos foram avaliados na procura de determinantes da homocisteinemia. A concentração sérica de homocisteína foi medida através da cromatografia de alta resolução e a concentração de ácido fólico e vitamina B12 por radio-imunoensaio. RESULTADOS: Os pacientes tinham 48.8 ± 15.1 aa e 43.3 ± 11.3 aa respectivamente, nos grupos I e II e os doadores 46.5 ± 14.8 aa. A homocisteinemia sérica média dos pacientes transplantados renais foi de 18.07 ± 8.29 mmol/l. No grupo de pacientes em uso de ciclosporina foi de 16.55 ± 5.6 mmol/l e no grupo sem ciclosporina foi de 21.44 ± 12.1 mmol/l (NS). No grupo de doadores foi significativamente menor (9.07 ± 3.06 mmol/l; grupo I + grupo II vs. grupo III, pPURPOSE: Hyperhomocyst(e)inaemia is an important risk factor for atherosclerosis, which is currently a major cause of death in renal transplant patients. The aim of this study was to assess the influence of immunosuppressive therapy on homocyst(e)inemia in renal transplant recipients. METHODS: Total serum homocysteine (by high performance liquid chromatography), creatinine, lipid profile, folic acid (by radioimmunoassay-RIA) and vitamin B12 (by RIA) concentrations were measured in 3 groups. Group I patients (n=20) were under treatment with cyclosporine, azathioprine, and prednisone; group II (n=9) were under treatment with azathioprine and prednisone; and group III (n=7) were composed of renal graft donors for groups I and II. Creatinine, estimated creatinine clearance, cyclosporine trough level, lipid profile, folic acid, and vitamin B12 concentrations and clinical characteristics of patients were assessed with the aim of ascertaining determinants of hyperhomocyst(e)inemia. RESULTS: Patient ages were 48.8 ± 15.1 yr (group I), 43.3 ± 11.3 yr (group II); and 46.5 ± 14.8 yr (group III). Mean serum homocyst(e)ine (tHcy) concentrations were 18.07 ± 8.29 mmol/l in renal transplant recipients; 16.55 ± 5.6 mmol/l and 21.44 ± 12.1 mmol/l respectively for group I (with cyclosporine) and group II (without cyclosporine) (NS). In renal donors, tHcy was significantly lower (9.07 ± 3.06 mmol/l; group I + group II vs. group III,

Jovens europeus: retrato da diversidade

This article explores the diversity of education to work transitions amongst some European young people. Following contextualisation of recent social change in issues relating to the family, individualized trajectories and transition regimes in Europe, youth transitions are discussed through the presentation of results of current qualitative research. This research is represented by exemplary case studies from six of the regions participating in this research, namely, Portugal, Denmark, the Netherlands, Italy, East Germany and the United Kingdom. These accounts illustrate the range of responses young people with contrasting social conditions across Europe make to changing circumstances, such as the extension and prolongation of educational pathways, the transformation of the labour market and a shifting balance between state and family support in enabling labour market entry. Dimensions such as family ties and future plans are also portrayed in this article in relation to current theoretical debates around the issues individualization, agency and structure in youth trajectories.Este artigo explora as transições para a vida adulta de jovens de várias regiões européias a partir de dados de uma pesquisa recente, baseada em um questionário. Para isso aplicaram-se análises tipológicas e fatoriais: das primeiras emergiram cinco grupos, tipificando distintas transições, orientações atitudinais e sociografias juvenis; das segundas resultaram contrastes fatoriais que evidenciam diferentes modalidades de transição. Essas análises - tipológicas e fatoriais - foram complementadas com análises qualitativas de entrevistas aprofundadas realizadas em uma amostra dos jovens inquiridos e seus respectivos pais. As triangulações analíticas ilustram a diversidade das transições, interpretadas à luz dos processos sociais (como a individualização e a reprodução social) e dos contextos de socialização (familiar, educacional, cultural)

A theoretical study on e--CO elastic collision using the configuration interaction method to describe the target

It is presented a theoretical study on electron -CO collisions in the (5-20) eV energy range. Specifically, elastic differential cross sections (DCS) are calculated using the configuration interaction (CI) method to describe the target. Static and exchange contributions to the interaction potential are obtained exactly from a CI wave function with single and double excitations. The DCS are obtained using the Schwinger variational iterative method (SVIM). It is observed that the discrepancies between Hartree-Fock and CI results are more significant for low energies and small angles

Daño pulmonar agudo en el parénquima pulmonar asociado al consumo de cigarrillo tradicional vs. cigarrillo electrónico

Introduction: Smoking is the main individual cause of preventable deaths in the world, so currently, due to the damage associated with tobacco, new alternatives to traditional cigarettes have been incorporated, such as electronic cigarettes; however, due to the consumption of these, there are new reports about the syndrome of lung injury associated with the use of electronic cigarettes or vaping products (EVALI) so this review seeks to detail which are these injuries that occur and compare them with the injuries of traditional cigarette consumption. Objective: The objective of the present investigation has been to carry out a review of the bibliography about the pathological characteristics that can be presented by the consumption of these devices. Methodology: A narrative bibliographic review was carried out about acute lung damage in the lung parenchyma associated with traditional cigarette consumption vs. electronic cigarette performing a search in different databases such as pubmed, scopus, elsevier. Development: It is thought that vitamin E acetate may be one of the substances found in electronic cigarette liquid that has the greatest association with EVALI; in turn, the sweeteners and flavorings used in these preparations increase the probability that people try or continue to use e-cigarette products facilitating the use of nicotine in these devices by masking the aversive properties of nicotine. Regarding the acute lesions found by traditional cigarettes, acute eosinophilic pneumonia was detailed, which, when compared with the pathological findings caused by EVALI, similarities such as type II pneumocyte hyperplasia, increased amount of intra-alveolar fibrin, and eosinophilic infiltration were observed. Conclusion: Both electronic and traditional cigarettes can present acute pathologies, differentiating them into acute eosinophilic pneumonia and EVALI, so the switch to electronic cigarettes does not present any benefit for the consumer. General area of study: Medicine. Specific area of study: Pneumology, Pathology.Introducción: El tabaquismo es la principal causa individual de muertes prevenibles en el mundo por lo que actualmente debido al daño asociado a tabaco se han incorporado nuevas alternativas a los cigarrillos tradicionales, como los cigarrillos electrónicos sin embargo, debido al consumo de estos, existen nuevos informes acerca del síndrome de lesión pulmonar asociado con el uso de cigarrillos electrónicos o productos de vapeo (EVALI) por lo que esta revisión busca detallar cuales son estas lesiones que se producen y compararlas con las lesiones del consumo de cigarrillo tradicional. Objetivo: El objetivo de la presente investigación ha sido realizar una revisión de la bibliografía acerca de las características patológicas que se pueden presentar por el consumo de estos dispositivos. Metodología: Se realizó  una  revisión  bibliográfica narrativa acerca  del  daño pulmonar agudo en el parénquima pulmonar asociado al consumo de cigarrillo tradicional vs. cigarrillo electrónico realizando una búsqueda en diferentes bases de datos como pubmed, scopus, elsevier. Desarrollo: Se piensa que el acetato de vitamina E puede ser uno de las sustancias que se encuentran en el líquido para cigarrillos electrónicos que tenga mayor asociación con EVALI, a su vez los endulzantes y saborizantes que se utilizan en estas preparaciones aumentar la probabilidad de que las personas prueben los productos de cigarrillos electrónicos o continúen usándolos facilitando el uso de nicotina en estos dispositivos ya que enmascaran las propiedades aversivas de la nicotina. En cuanto a las lesiones agudas encontradas por cigarrillo tradicional se detalló la neumonía eosinofílica aguda, la cual comparándola con los hallazgos patológicos causados por EVALI se observó similitudes como la hiperplasia de neumocitos tipo II, el aumento de la cantidad de fibrina intraalveolar e infiltración eosinofílica. Conclusión: Tanto los cigarillos electrónicos como los tradicionales pueden llega a presentar patologías agudas, diferenciandolas en neumonía eosinofílica aguda y EVALI por lo que el cambio a cigarrillos electrónicos no presenta ningun beneficio para el consumidor. Área   de   estudio   general: medicina. Área de estudio específica: Neumología, Patología

Self-secured devices: high performance and secure I/O access in TrustZone-based systems

Arm TrustZone is a hardware technology that adds significant value to the ongoing security picture. TrustZone-based systems typically consolidate multiple environments into the same platform, requiring resources to be shared among them. Currently, hardware devices on TrustZone-enabled system-on-chip (SoC) solutions can only be configured as secure or non-secure, which means the dual-world concept of TrustZone is not spread to the inner logic of the devices. The traditional passthrough model dictates that both worlds cannot use the same device concurrently. Furthermore, existing shared device access methods have been proven to cause a negative impact on the overall system in terms of security and performance.This work introduces the concept of self-secured devices, a novel approach for shared device access in TrustZone-based architectures. This concept extends the TrustZone dual-world model to the device itself, providing a secure and non-secure logical interface in a single device instance. The solution was deployed and evaluated on the LTZVisor, an open-source and lightweight TrustZone-assisted hypervisor. The obtained results are encouraging, demonstrating that our solution requires only a few additional hardware resources when compared with the native device implementation, while providing a secure solution for device sharing.This work has been supported by FCT -Fundação para a Ciência e a Tecnologia, Portugal within the R&D Units Project Scope: UIDB/00319/2020