134 research outputs found

    Aspect-oriented fault tolerance for real-time embedded systems

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    Real-time embedded systems for safety-critical applications have to introduce fault tolerance mechanisms in order to cope with hardware and software errors. Fault tolerance is usually applied by means of redundancy and diversity. Redundant hardware implies the establishment of a distributed system executing a set of fault tolerance strategies by software, and may also employ some form of diversity, by using different variants or versions for the same processing. This paper describes our approach to introduce fault tolerance in distributed embedded systems applications, using aspect-oriented programming (AOP). A real-time operating system sup-porting middleware thread communication was integrated to a fault tolerant framework. The introduction of fault tolerance in the system is performed by AOP at the application thread level. The advantages of this approach include higher modularization, less efforts for legacy systems evolution and better configurability for testing and product line development. This work has been tested and evaluated successfully in several fault tolerant configurations and presented no significant performance or memory footprint costs.Fundação para a Ciência e a Tecnologia (FCT

    Anatomo-fisiopatologia da circulação feto-placentar : Implicações clínicas da fluxometria Doppler

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    Dissertação de Doutoramento em Medicina, área de especialização em Ginecologia e Obstetrícia, apresentada à Faculdade de Medicina da Universidade do Port

    Problemas e desafios no exercício da actividade docente : um estudo sobre o stresse, “burnout”, saúde física e satisfação profissional em professores do 3º ciclo e ensino secundário

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    O presente trabalho apresenta dados de um estudo realizado com 127 professores de uma escola secundária do Distrito do Porto, onde se avaliaram vários indicadores relacionados com o trabalho e o bem-estar pessoal (stresse, “burnout”, saúde física e satisfação profissional). Os resultados revelaram valores muito significativos de stresse ocupacional (percentagens acima dos 30%), uma prevalência de esgotamento de 13% e vários problemas de saúde física. Também se verificou que as mulheres demonstraram níveis superiores de stresse associados às pressões de tempo e excesso de trabalho, mais queixas relativamente ao trabalho burocrático/administrativo bem como níveis mais elevados de exaustão emocional e problemas físicos, enquanto que os homens evidenciaram uma maior tendência para a despersonalização. Na distinção dos professores em função da experiência profissional, observou-se que os que tinham mais anos de trabalho assumiram mais problemas em lidar com os comportamentos de indisciplina dos alunos, as disparidades nas capacidades apresentadas pelos alunos e o trabalho burocrático/administrativo e excesso de aulas. Finalmente, os professores com mais horas de contacto com os alunos apresentaram menos despersonalização e mais stresse relacionado com a indisciplina dos alunos e o estatuto da carreira docente

    Objectively assessed physical activity and sedentary behaviour during pregnancy in portuguese women:Differences between trimesters and weekdays and weekends

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    Background: Engaging in physical activity (PA) and reducing sedentary behaviour (SB) are important for health during pregnancy, yet relatively few studies have examined these variables using objective measures and across trimesters during pregnancy. Objective: To determine the amount of objectively assessed PA and SB engaged in whether there was any weekday to weekend day variation in PA and SB during the first and second trimester of pregnancy. Method: PA and SB were determined using accelerometry worn over 7 consecutive days during each trimester in 137 Portuguese females (mean age ± SD = 29.6 ± 5.7). Results: In regard to the proportion of participants meeting the ACSM guidelines for PA, 37.5% of the participants in the first trimester and 29.6% of participants in the second trimester met the cut off of 30min or more of any type of moderate intensity activity on most (5) days of the week. Moderate intensity PA was significantly lower in trimester 2 compared to trimester 1 (P = 0.003). Moderate intensity PA was also significantly lower during weekends compared to weekdays irrespective of trimester (P = 0.003). SB, light and vigorous intensity PA were relatively stable from trimester 1 to trimester 2 and between weekdays and weekends (P < 0.05). Conclusion: The present study suggests that the majority of women do not meet PA guidelines for health during pregnancy and that moderate intensity PA declines form trimester 1 to 2 and is lower at weekends

    Photoswitchable Calixarene Activators for Controlled Peptide Transport across Lipid Membranes

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    Funding Information: This work was supported by the Associate Laboratory for Green Chemistry-LAQV (projects UIDB/50006/2020 and UIDP/50006/2020), which is financed by national funds from FCT/MCTES. FCT/MCTES is also acknowledged for supporting the National Portuguese NMR Network (ROTEIRO/0031/2013-PINFRA/22161/2016, cofinanced by FEDER through COMPETE 2020, POCI, PORL, and FCT through PIDDAC) and for the projects PTDC/QUI-COL/32351/2017, 2022.02538.PTDC, and the CEECIND/00466/2017 research contract (N.B.). J.N.M. acknowledges FCT for the PhD grant (2021.06296.BD). J.M. thanks the Spanish Agencia Estatal de Investigación (AEI) [PCI2019-103400 and PID2020-117143RB-I00], Xunta de Galicia (ED431C 2017/25 and ED431G 2019/03), and the ERDF. J.M. received an ERC-Stg (DYNAP, 677786), ERC-POC (TraffikGene, 838002), Xunta de Galicia (Oportunius Program), and HFSP-YIG (RGY0066/2017). Y.F.-C. and A.R. thank the AEI for the FPU fellowships (FPU21/04747) and (FPU18/03192), respectively. We acknowledge Dr. João Carlos Lima for fruitful scientific discussions. Publisher Copyright: © 2023 The Authors. Published by American Chemical Society.Supramolecular synthetic transporters are crucial to understand and activate the passage across lipid membranes of hydrophilic effector molecules. Herein, we introduce photoswitchable calixarenes for the light-controlled transport activation of cationic peptide cargos across model lipid bilayers and inside living cells. Our approach was based on rationally designed p-sulfonatocalix[4]arene receptors equipped with a hydrophobic azobenzene arm, which recognize cationic peptide sequences at the nM range. Activation of membrane peptide transport is confirmed, in synthetic vesicles and living cells, for calixarene activators featuring the azobenzene arm in the E configuration. Therefore, this method allows the modulation of the transmembrane transport of peptide cargos upon Z-E photoisomerization of functionalized calixarenes using 500 nm visible light. These results showcase the potential of photoswitchable counterion activators for the light-triggered delivery of hydrophilic biomolecules and pave the way for potential applications in remotely controlled membrane transport and photopharmacology applications of hydrophilic functional biomolecules.publishersversionpublishe

    Unruptured ectopic pregnancy: diagnosis and treatment. State of art

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    It is advisable to do the non-invasive diagnosis of ectopic pregnancy precociously, before there is the tube rupture, combining for that the transvaginal ultrasonography with the dosage of the b-fraction of the chorionic gonadotrophin. A range of treatment options may be used. Either a surgical intervention or a clinical treatment may be taken into consideration. Laparotomy is indicated in cases of hemodynamic instability. Laparoscopy is the preferential route for the treatment of tube pregnancy. Salpingectomy should be performed in patients having the desired number of children, while salpingostomy should be indicated in patients willing to have more children, when the b-hCG titers are under 5,000 mUI/mL and the surgical conditions are favorable. The use of methotrexate (MTX) is a consecrated clinical procedure and should be indicated as the first option of treatment. The main criteria for MTX indication are hemodynamic stability, b-hCG 5,000 mUI/mL and no alive embryo. Indication for local treatment with an injection of MTX (1 mg/kg) guided by transvaginal ultrasonography should occur in cases of alive embryos, but with an atypical localization. An expectant conduct should be indicated in cases of decrease in the b-hCG titers within 48 hous before the treatment, and when the initial titers are under 1,500 mUI/mL. There are controversies between salpingectomy and salpingostomy, concerning the reproductive future. Till we reach an agreement in the literature, the advice to patients who are looking forward to a future gestation, is to choose either surgical or clinical conservative conducts.O diagnóstico não invasivo da gravidez ectópica deve ser realizado precocemente, antes de ocorrer a ruptura tubária, combinando a ultra-sonografia transvaginal com a dosagem da fração beta do hormônio gonadotrófico coriônico. Diversas opções de tratamento podem ser utilizadas. Devemos respeitar as indicações tanto das intervenções cirúrgicas como do tratamento clínico. A laparotomia está indicada nos casos de instabilidade hemodinâmica. A laparoscopia é a via preferencial para o tratamento da gravidez tubária. A salpingectomia deve ser realizada nas pacientes com prole constituída. A salpingostomia é indicada nas pacientes com desejo reprodutivo, quando os títulos da b-hCG forem inferiores a 5000 mUI/mL e as condições cirúrgicas forem favoráveis. O tratamento com metotrexato (MTX) é uma conduta consagrada, podendo ser indicado como primeira opção de tratamento. Os principais critérios para indicação do MTX são estabilidade hemodinâmica, b-hCG 5.000 mUI/mL e ausência de embrião vivo. A indicação do tratamento local com injeção de MTX (1 mg/kg) guiada por ultra-sonografia transvaginal é na presença de embrião vivo nos casos de localização atípica. A conduta expectante deve ser indicada nos casos de declínio dos títulos da b-hCG em 48 horas antes do tratamento e quando os títulos iniciais são inferiores a 1.500 mUI/mL. Em relação ao futuro reprodutivo, existem controvérsias entre a salpingectomia e a salpingostomia. Até obtermos um consenso na literatura, orientamos às pacientes desejosas de uma futura gestação a optar pelas condutas conservadoras, tanto cirúrgicas como clínicas.Universidade Federal de São Paulo (UNIFESP) Departamento de ObstetríciaHospital São JoãoUniversidade do Porto Faculdade de MedicinaUniversidade Federal de São Paulo (UNIFESP)UNIFESP, Depto. de ObstetríciaUNIFESPSciEL

    Sex differences in the fetal heart rate variability indices of twins

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    Aims: To evaluate the differences in linear and complex heart rate dynamics in twin pairs according to fetal sex combination [male-female (MF), male-male (MM), and female-female (FF)]. Methods: Fourteen twin pairs (6 MF, 3 MM, and 5 FF) were monitored between 31 and 36.4 weeks of gestation. Twenty-six fetal heart rate (FHR) recordings of both twins were simultaneously acquired and analyzed with a system for computerized analysis of cardiotocograms. Linear and nonlinear FHR indices were calculated. Results: Overall, MM twins presented higher intrapair average in linear indices than the other pairs, whereas FF twins showed higher sympathetic-vagal balance. MF twins exhibited higher intrapair average in entropy indices and MM twins presented lower entropy values than FF twins considering the (automatically selected) threshold rLu. MM twin pairs showed higher intrapair differences in linear heart rate indices than MF and FF twins, whereas FF twins exhibited lower intrapair differences in entropy indices. Conclusions: The results of this exploratory study suggest that twins have sex-specific differences in linear and nonlinear indices of FHR. MM twins expressed signs of a more active autonomic nervous system and MF twins showed the most active complexity control system. These results suggest that fetal sex combination should be taken into consideration when performing detailed evaluation of the FHR in twins.This work was supported by a grant (SFRH/BD/40146/2007) to the first author from Fundacao para a Ciencia e Tecnologia. Hernani Goncalves is financed by a postdoctoral grant (SFRH/BPD/69671/2010) from the Fundacao para a Ciencia e a Tecnologia (FCT), Portugal
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