137 research outputs found

    Dissemination of contextual information for assisted driving

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    Mestrado em Engenharia Electrónica e TelecomunicaçõesDriver assistance systems can be used to improve road and car safety, reduce driving fatigue and provide a more e cient driving experience. An important part of these systems is the communication between vehicles, and vehicle-to-infrastructure communication. This work presents mechanisms enabling driving support, exploring the vehicular network to provide information about the drivers neighborhood. The network is composed by vehicles, tra c signals and xed stations along the road. Each car is equipped with a recording camera, a GPS receiver, as well as communication modules such as WiFi, WAVE and 3G/4G, allowing the exchange of data between the various nodes. The data exchanged is composed by positional data of neighboring vehicles, sensor information from tra c signals and video images incoming from other vehicles. This data is used to facilitate the driver in decision making, but can also provide an overview of the tra c density in the neighborhood. The tra c signals broadcast their position and if they are dynamic (such as tra c lights), their status is also transmitted. The xed stations are equipped with numerous sensors and are used to provide environmental data. The driver can access all the collected data via visual information, on a display screen that contains a map of the neighborhood along with the information available of the nearby nodes. The proposed system is evaluated through real vehicular experiments in two distinct scenarios: urban and highway. The results show that the communication delay is higher in the highway scenario, mainly due to the distance between vehicles and travelling speeds. However, promising results regarding the maximum delay and the average number of retransmissions foresee important inputs for future services of assisted-driving, in general, and carovertaking assistance, in particular.Os sistemas de condução assistida podem ser utilizados para melhorar a segurança rodoviária e automóvel, reduzir a fadiga da condução e proporcionar uma experiência de condução mais e ciente. Uma parte importante desses sistemas e a comunicação entre veículos e comunicação veiculo infraestrutura. Este trabalho propõe mecanismos que permitem o suporte a condução, explorando a rede de veicular para fornecer informações sobre a vizinhança do condutor. A rede e composta por veículos, sinais de transito e estações fixas ao longo da estrada. Cada carro esta equipado com uma camera de gravação, um receptor GPS, bem como módulos de comunicação, como WiFi, WAVE e 3G/4G, permitindo a troca de dados entre os vários nos. Os dados trocados são compostos por dados posicionais de veículos vizinhos, informações sensoriais de sinais de trânsito e imagens de vídeo provenientes de outros veículos. Esses dados s~ao usados para facilitar a tomada de decisões, mas também podem fornecer uma vis~ao geral da densidade de tráfego na vizinhança. Os sinais de transito transmitem a sua posição e, no caso de serem dinâmicos (como semáforos), o seu estado actual também e transmitido. As estações fixas estão equipadas com vários sensores e sao usadas para fornecer dados ambientais. O condutor pode aceder a todos os dados recolhidos através de informações visuais, num ecrã que contém um mapa da sua redondeza junto com a informação disponível dos nos vizinhos. O sistema proposto e avaliado através de testes reais em dois cenários distintos: urbano e auto-estrada. Os resultados mostram que o atraso da comunicação e maior no cenário da auto-estrada, principalmente devido as maiores distancias entre os veículos e as velocidades mais elevadas. No entanto, resultados promissores em relação ao atraso máximo e ao numero médio de retransmissões prevêem contribuições importantes para serviços futuros de condução assistida em geral, e assistência de ultrapassagem de veículos, em particular

    Framework de rede tolerante a falhas

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    Dissertação de mestrado integrado em Engenharia InformáticaUma Fault Tolerant Network é uma estrutura de Redes que tem como objetivo garantir a comunicação entre Nodos de uma Rede mesmo que esta seja propícia à perda de Datagramas e à consequente perda de Informação. Estas perdas podem acontecer por vários motivos, mas este projeto tem como alvo analisar três casos, o da mobilidade de Nodos na Rede, o da conexão intermitente e o da conexão esporádica. Todos estes ambientes onde se pretende assegurar a troca de Informação entre Nodos apresentam uma característica em comum, um possível volume elevado de perda de Datagramas a qualquer instante que limita a quantidade de Dados que podem ser trocados bem como a Qualidade de Serviço destas mesmas trocas de Dados. Esta é a principal característica que se pretende atenuar com o desenvolvimento deste Projeto, porém existem outras relacionadas como a interrupção prolongada de uma Transmissão e a sua retoma que também foram analisadas. Como todos os ambientes referidos anteriormente apresentam adversidades semelhantes ou que podem ser tratadas como tal, optou-se pelo desenvolvimento de um Protocolo de Transferência de Dados adaptado a tais adversidades. Este encontra-se entre a Camada de Transporte e a Camada de Aplicações da Network Stack e pode ser utilizado como base para o Desenvolvimento de Arquiteturas que possibilitem a Troca organizada de Informação entre Nodos. Neste Projeto foi Desenhado e Implementado um Protocolo de Transferência de Dados que possibilita a troca de informação nos ambientes anteriormente referidos, apresentando resiliência a Drops de Datagramas, grandes Delays na transmissão destes e movimentações de Nodos na Rede. Para além deste Protocolo, foi Desenhada uma simples Arquitetura de Redes baseada em Redes Ad Hoc onde cada Nodo tem uma visualização da Rede centralizada nele próprio e os restantes Nodos visíveis encontram-se organizados em Níveis de Vizinhança consoante a sua distância ao Nodo central. Foi tamb´em definido o objetivo de desenho de uma Arquitetura de Redes baseada em Redes DTN, que fortemente influenciou o Protocolo de Transferência de dados devido às suas grandes exigências. Por fim foram realizados testes em determinados cenários reais pertinentes ao Protótipo Implementado de forma a provar que os objetivos delineados inicialmente foram atingidos.A Fault Tolerant Network is a Network structure that aims to guarantee Node communication in certain Network environments that are prone to Datagram Drops and consequent loss of Information. These Drops can be present due to a multitude of reasons but this Project aims to analyze three specific cases where these can occur, Node Mobility, Intermittent Network Connection and Sporadic Network Connection. All these cases present the same challenge to Node Communication, there’s a possibility of a high volume of Datagram Drops that can happen unexpectedly, limits the amount of Data that can be exchanged between Nodes and lowers the Quality of Service of said exchanges. The main objective of this Project is to address these limitations that are innate in these specific cases as well as other topics that are derivative of said limitations such as extensive interruptions in Data Transfers and subsequent resume of these. Since all the cases described previously present the same challenges, or they can be treated like they are similar, it was decided to develop a Data Transfer Protocol fitted for these limitations. This Protocol is between the Transport and Application Layers of the Network Stack and it’s purpose is to improve Data Transfer and Reception between Nodes. In this Project, a Data Transfer Protocol was designed and implemented that enables Data transmission between Nodes in the cases previously referred, showing resilience against Datagram Drops, Transmission Delays and Node Mobility. In addition to this Protocol, a simple Ad Hoc Network Architecture was designed using said Protocol where each Node has a view of the Network centralized onto itself and the Neighboring Nodes organized in Neighbor Levels depending on their distance to the central Node. The objective of designing a simple version of a DTN was also established bringing new challenges that strongly influenced the design of the Data Transfer Protocol due to its strict requirements. Lastly, some tests were performed in real world scenarios in such ways that all the features designed and developed in this Project could be shown to be working properly and that all objectives delined were met

    Quantification of cell cycle kinetics by EdU (5-ethynyl-2′-deoxyuridine)-coupled-fluorescence-intensity analysis

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    Copyright: Pereira et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License 3.0 (CC BY3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.We propose a novel single-deoxynucleoside-based assay that is easy to perform and provides accurate values for the absolute length (in units of time) of each of the cell cycle stages (G1, S and G2/M). This flow-cytometric assay takes advantage of the excellent stoichiometric properties of azide-fluorochrome detection of DNA substituted with 5-ethynyl-2'-deoxyuridine (EdU). We show that by pulsing cells with EdU for incremental periods of time maximal EdU-coupled fluorescence is reached when pulsing times match the length of S phase. These pulsing times, allowing labelling for a full S phase of a fraction of cells in asynchronous populations, provide accurate values for the absolute length of S phase. We characterized additional, lower intensity signals that allowed quantification of the absolute durations of G1 and G2 phases.Importantly, using this novel assay data on the lengths of G1, S and G2/M phases are obtained in parallel. Therefore, these parameters can be estimated within a time frame that is shorter than a full cell cycle. This method, which we designate as EdU-Coupled Fluorescence Intensity (E-CFI) analysis, was successfully applied to cell types with distinctive cell cycle features and shows excellent agreement with established methodologies for analysis of cell cycle kinetics.João A. Ferreira received support from a Calouste Gulbenkian Foundation grant (96526) and Pedro Pereira is an FCT fellow (SFRH/BD/45502/2008). Evguenia Bekman is the recipient of an IMM-Lisbon fellowship (iMM/BPD/60-2016; project PTDC/BEXBCM/5899/2014).info:eu-repo/semantics/publishedVersio

    Thrombus aspiration in patients with ST-elevation myocardial infarction: results of a national registry of interventional cardiology

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    BACKGROUND: We aimed to evaluate the impact of thrombus aspiration (TA) during primary percutaneous coronary intervention (P-PCI) in 'real-world' settings. METHODS: We performed a retrospective study, using data from the National Registry of Interventional Cardiology (RNCI 2006-2012, Portugal) with ST-elevation myocardial infarction (STEMI) patients treated with P-PCI. The primary outcome, in-hospital mortality, was analysed through adjusted odds ratio (aOR) and 95% confidence intervals (95%CI). RESULTS: We assessed data for 9458 STEMI patients that undergone P-PCI (35% treated with TA). The risk of in-hospital mortality with TA (aOR 0.93, 95%CI:0.54-1.60) was not significantly decreased. After matching patients through the propensity score, TA reduced significantly the risk of in-hospital mortality (OR 0.58, 95%CI:0.35-0.98; 3500 patients). CONCLUSIONS: The whole cohort data does not support the routine use of TA in P-PCI, but the results of the propensity-score matched cohort suggests that the use of selective TA may improve the short-term risks of STEMI..info:eu-repo/semantics/publishedVersio

    Nationwide access to endovascular treatment for acute ischemic stroke in portugal

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    Publisher Copyright: Copyright Ordem dos M dicos 2021.Introduction: Since the publication of endovascular treatment trials and European Stroke Guidelines, Portugal has re-organized stroke healthcare. The nine centers performing endovascular treatment are not equally distributed within the country, which may lead to differential access to endovascular treatment. Our main aim was to perform a descriptive analysis of the main treatment metrics regarding endovascular treatment in mainland Portugal and its administrative districts. Material and Methods: A retrospective national multicentric cohort study was conducted, including all ischemic stroke patients treated with endovascular treatment in mainland Portugal over two years (July 2015 to June 2017). All endovascular treatment centers contributed to an anonymized database. Demographic, stroke-related and procedure-related variables were collected. Crude endovascular treatment rates were calculated per 100 000 inhabitants for mainland Portugal, and each district and endovascular treatment standardized ratios (indirect age-sex standardization) were also calculated. Patient time metrics were computed as the median time between stroke onset, first-door, and puncture. Results: A total of 1625 endovascular treatment procedures were registered. The endovascular treatment rate was 8.27/100 000 inhabitants/year. We found regional heterogeneity in endovascular treatment rates (1.58 to 16.53/100 000/year), with higher rates in districts closer to endovascular treatment centers. When analyzed by district, the median time from stroke onset to puncture ranged from 212 to 432 minutes, reflecting regional heterogeneity. Discussion: Overall endovascular treatment rates and procedural times in Portugal are comparable to other international registries. We found geographic heterogeneity, with lower endovascular treatment rates and longer onset-to-puncture time in southern and inner regions. Conclusion: The overall national rate of EVT in the first two years after the organization of EVT-capable centers is one of the highest among European countries, however, significant regional disparities were documented. Moreover, stroke-onset-to-first-door times and in-hospital procedural times in the EVT centers were comparable to those reported in the randomized controlled trials performed in high-volume tertiary hospitalspublishersversionpublishe

    Acesso a Tratamento Endovascular para Acidente Vascular Cerebral Isquémico em Portugal

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    Introduction: Since the publication of endovascular treatment trials and European Stroke Guidelines, Portugal has re-organized stroke healthcare. The nine centers performing endovascular treatment are not equally distributed within the country, which may lead to differential access to endovascular treatment. Our main aim was to perform a descriptive analysis of the main treatment metrics regarding endovascular treatment in mainland Portugal and its administrative districts. Material and Methods: A retrospective national multicentric cohort study was conducted, including all ischemic stroke patients treated with endovascular treatment in mainland Portugal over two years (July 2015 to June 2017). All endovascular treatment centers contributed to an anonymized database. Demographic, stroke-related and procedure-related variables were collected. Crude endovascular treatment rates were calculated per 100 000 inhabitants for mainland Portugal, and each district and endovascular treatment standardized ratios (indirect age-sex standardization) were also calculated. Patient time metrics were computed as the median time between stroke onset, first-door, and puncture. Results: A total of 1625 endovascular treatment procedures were registered. The endovascular treatment rate was 8.27/100 000 inhabitants/year. We found regional heterogeneity in endovascular treatment rates (1.58 to 16.53/100 000/year), with higher rates in districts closer to endovascular treatment centers. When analyzed by district, the median time from stroke onset to puncture ranged from 212 to 432 minutes, reflecting regional heterogeneity. Conclusion: The overall national rate of EVT in the first two years after the organization of EVT-capable centers is one of the highest among European countries, however, significant regional disparities were documented. Moreover, stroke-onset-to-first-door times and in-hospital procedural times in the EVT centers were comparable to those reported in the randomized controlled trials performed in high-volume tertiary hospitals.Introdução: A aprovação do tratamento endovascular para o acidente vascular cerebral isquémico obrigou à reorganização dos cuidados de saúde em Portugal. Os nove centros que realizam tratamento endovascular não estão distribuídos equitativamente pelo território, o que poderá causar acesso diferencial a tratamento. O principal objetivo deste estudo é realizar uma análise descritiva da frequência e métricas temporais do tratamento endovascular em Portugal continental e seus distritos. Material e Métodos: Estudo de coorte nacional multicêntrico, incluindo todos os doentes com acidente vascular cerebral isquémico submetidos a tratamento endovascular em Portugal continental durante um período de dois anos (julho 2015 a junho 2017). Foram colhidos dados demográficos, relacionados com o acidente vascular cerebral e variáveis do procedimento. Taxas de tratamento endovascular brutas e ajustadas (ajuste indireto a idade e sexo) foram calculadas por 100 000 habitantes/ano para Portugal continental e cada distrito. Métricas de procedimento como tempo entre instalação, primeira porta e punção foram também analisadas. Resultados: Foram registados 1625 tratamentos endovasculares, indicando uma taxa bruta nacional de tratamento endovascular de 8,27/100 000 habitantes/ano. As taxas de tratamento endovascular entre distritos variaram entre 1,58 e 16,53/100 000/ano, com taxas mais elevadas nos distritos próximos a hospitais com tratamento endovascular. O tempo entre sintomas e punção femural entre distritos variou entre 212 e 432 minutos. Conclusão: Portugal continental apresenta uma taxa nacional de tratamento endovascular elevada, apresentando, contudo, assimetrias regionais no acesso. As métricas temporais foram comparáveis com as observadas nos ensaios clínicos piloto

    MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

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    Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

    Neoplasia maligna da mama em mulheres no Brasil: aspectos epidemiológicos, diagnóstico e tratamento

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    This article aims to evaluate the epidemiological aspects, diagnosis and treatment of patients with malignant breast neoplasia. This is an integrative review using the BVS, SciELO, LILACS and PubMed as databases over the last 5 years. 272 articles on the topic were evaluated with an emphasis on a synthesis of the most recent knowledge and greater scientific consistency. Breast cancer must be approached by a multidisciplinary team aiming at comprehensive treatment of the patient. It is concluded that this neoplasm stands out as one of the most serious public health problems in Brazil. Early diagnosis of breast cancer, aiming to evaluate the best treatment possibilities for these young patients, can have fewer impacts on their personal and social lives.Este artigo tem por objetivo avaliar os aspectos epidemiológicos, diagnóstico e tratamento das pacientes com neoplasia maligna da mama. Trata-se de uma revisão integrativa utilizando como base de dados a BVS, a SciELO, o LILACS e o PubMed, nos últimos 5 anos. Foram avaliados 272 artigos sobre o tema com ênfase em uma síntese dos conhecimentos mais recentes e de maior consistência científica. O câncer de mama deve ser abordado por uma equipe multidisciplinar visando ao tratamento integral da paciente. Conclui-se que essa neoplasia destaca-se como um dos mais graves problemas de saúde pública do Brasil. O diagnóstico precoce do câncer de mama, visando avaliar as melhores possibilidades de tratamento para essas pacientes jovens, pode proporcionar menores impactos na sua vida pessoal e social
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