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This article presents an innovative approach to the design of a safe adaptive backstepping control system. Tailored specifically for underactuated marine robots, the system utilizes simple sensors for enhanced practicality and efficiency. Given their operation in diverse oceanic environments fraught with various sources of uncertainties, ensuring the system's safe and robust behavior holds paramount importance in the control literature. To address this concern, this paper introduces a control strategy designed to ensure robustness at both the kinematic and dynamic levels. By emphasizing the compensation for the system uncertainties, the design integrates a straightforward fuzzy system structure. To further ensure the system's safety, a funnel surface is defined, followed by the design of a suitable nonlinear sliding surface as a function of the funnel and tracking error. Using Lyapunov theory, the study formally establishes the Semi-globally Practically Finite-time Stability of the closed-loop system, validated through simulations conducted on underactuated marine robots.
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Sessile organisms, such as plants, developed various ways to sense and respond to external and internal stimuli to maximize their fitness through evolutionary time. Transcripts and protein regulation are, among many, the main mechanisms that plants use to respond to environmental changes. SKIP protein is one such, presenting an SNKW interacting domain, which is highly conserved among eukaryotes, where SKI interacting protein acts in regulating key processes. In the present work, many bioinformatics tools, such as phylogenetic relationships, gene structure, physical-chemical properties, conserved motifs, prediction of regulatory cis-elements, chromosomal localization, and protein-protein interaction network, were used to better understand the genome-wide SNW/SKIP domain-containing proteins. In total, 28 proteins containing the SNW/SKIP domain were identified in different plant species, including plants of agronomic interest. Two main protein clusters were formed in phylogenetic analysis, and gene structure analysis revealed that, in general, the coding region had no introns. Also, expression of these genes is possibly induced by abiotic stress stimuli. Primary structure analysis of the proteins revealed the existence of an evolutionarily conserved functional unit. But physicochemical properties show that proteins containing the SNW/SKIP domain are commonly unstable under in vivo conditions. In addition, the protein network, demonstrated that SKIP homologues could act by modulating plant fitness through gene expression regulation at the transcriptional and post-transcriptional levels. This could be corroborated by the expression number of gene copies of SKIP proteins in many species, highlighting it's crucial role in plant development and tolerance through the course of evolution.
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Genoma de Planta , Filogenia , Proteínas de Plantas , Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , Domínios Proteicos , Regulação da Expressão Gênica de PlantasAssuntos
Diagnóstico Tardio , Aceitação pelo Paciente de Cuidados de Saúde , Tuberculose , Humanos , Masculino , Feminino , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adulto , Tuberculose/diagnóstico , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Inquéritos e Questionários , Comportamentos Relacionados com a SaúdeRESUMO
Closed-loop neuronal stimulation has a strong therapeutic potential for neurological disorders such as Parkinson's disease. However, at the moment, standard stimulation protocols rely on continuous open-loop stimulation and the design of adaptive controllers is an active field of research. Delayed feedback control (DFC), a popular method used to control chaotic systems, has been proposed as a closed-loop technique for desynchronisation of neuronal populations but, so far, was only tested in computational studies. We implement DFC for the first time in neuronal populations and access its efficacy in disrupting unwanted neuronal oscillations. To analyse in detail the performance of this activity control algorithm, we used specialised in vitro platforms with high spatiotemporal monitoring/stimulating capabilities. We show that the conventional DFC in fact worsens the neuronal population oscillatory behaviour, which was never reported before. Conversely, we present an improved control algorithm, adaptive DFC (aDFC), which monitors the ongoing oscillation periodicity and self-tunes accordingly. aDFC effectively disrupts collective neuronal oscillations restoring a more physiological state. Overall, these results support aDFC as a better candidate for therapeutic closed-loop brain stimulation.
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Estimulação Encefálica Profunda , Doença de Parkinson , Humanos , Retroalimentação , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Algoritmos , Neurônios/fisiologiaRESUMO
OBJECTIVES: This study evaluated the effectiveness of COVID-19 vaccines in preventing symptomatic and severe disease. STUDY DESIGN: This was an observational test-negative case-control study. METHODS: Study participants were adults with at least one symptom included in the World Health Organization COVID-19 definition who sought health care in a public emergency department between 1 November 2021 and 2 March 2022 (corresponding with the fifth pandemic wave in Portugal dominated by the Omicron variant). This study used multivariable logistic regression models to estimate and compare the odds ratio of vaccination between test-positive cases and test-negative controls to calculate the absolute and relative vaccine effectiveness. RESULTS: The study included 1059 individuals (522 cases and 537 controls) with a median age of 56 years and 58% were women. Compared with the effectiveness of the primary vaccination scheme that had been completed ≥180 days earlier, the relative effectiveness against symptomatic infection of a booster administered between 14 and 132 days earlier was 71% (95% confidence interval [CI]: 57%, 81%; P < 0.001). The effectiveness of the primary series against symptomatic infection peaked at 85% (95% CI: 56%, 95%) between 14 and 90 days after the last inoculation and decreased to 34% (95% CI: -43%, 50%) after ≥180 days. CONCLUSIONS: Despite the known immunological evasion characteristics of the Omicron variant, results from this study show that vaccine effectiveness increases after booster administration. COVID-19 vaccine effectiveness decreases to less than 50% between 3 and 6 months after completion of the primary cycle; therefore, this would be an appropriate time to administer a booster to restore immunity.
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Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Vacinas contra COVID-19/uso terapêutico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos de Casos e Controles , SARS-CoV-2Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Estações do Ano , Pandemias , Surtos de DoençasRESUMO
OBJECTIVE: We aimed to identify areas of high tuberculosis (TB) diagnosis delay in mainland Portugal in 2017 and ecological factors associated with these areas. STUDY DESIGN: This was an ecological study. METHODS: We considered all notified pulmonary TB cases from the Portuguese National Tuberculosis Surveillance System in mainland Portugal. Diagnostic delays were calculated at the municipality level. Demographic variables, proxies for TB awareness, health services capacity indicators, and socio-economic variables were included and extracted from official databases, such as Statistics Portugal, Ministeries, Foreigners and Border Services. We used spatial analysis to identify areas of high delay in 2017 and logistic generalised additive models to identify ecological factors associated with the identified cluster. RESULTS: We identified an area of high delay in 2017 in the South region of the country. Overall, municipalities with a smaller population density, smaller proportion of unemployed, fewer health centres and higher old-age dependency ratio, proportion of men, TB incidence, proportion of immigrants and high school dropout had a higher probability of belonging in a high delay area. CONCLUSION: The role of primary health care in TB diagnosis should be further explored. Interventions should address factors interplaying at the local and individual levels. Policies influencing social and health conditions, leading to changes in individual behaviour, can lead to sustained improvements over time.
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Emigrantes e Imigrantes , Tuberculose Pulmonar , Tuberculose , Diagnóstico Tardio , Humanos , Incidência , Masculino , Tuberculose/epidemiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologiaRESUMO
This article addresses the problem of path following of marine vehicles along straight lines in the presence of currents by resorting to an inner-outer control loop strategy, with due account for the presence of currents. The inner-outer loop control structures exhibit a fast-slow temporal scale separation that yields simple "rules of thumb" for controller tuning. Stated intuitively, the inner-loop dynamics should be much faster than those of the outer loop. Conceptually, the procedure described has three key advantages: (i) it decouples the design of the inner and outer control loops, (ii) the structure of the outer-loop controller does not require exact knowledge of the vehicle dynamics, and (iii) it provides practitioners a very convenient method to effectively implement path-following controllers on a wide range of vehicles. The path-following controller discussed in this article is designed at the kinematic outer loop that commands the inner loop with the desired heading angles while the vehicle moves at an approximately constant speed. The key underlying idea is to provide a seamless implementation of path-following control algorithms on heterogeneous vehicles, which are often equipped with heading autopilots. To this end, we assume that the heading control system is characterized in terms of an IOS-like relationship without detailed knowledge of vehicle dynamics parameters. This paper quantitatively evaluates the combined inner-outer loop to obtain a relationship for assessing the combined system's stability. The methods used are based on nonlinear control theory, wherein the cascade and feedback systems of interest are characterized in terms of their IOS properties. We use the IOS small-gain theorem to obtain quantitative relationships for controller tuning that are applicable to a broad range of marine vehicles. Tests with AUVs and one ASV in real-life conditions have shown the efficacy of the path-following control structure developed.
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Algoritmos , Simulação por Computador , RetroalimentaçãoRESUMO
BACKGROUND: In Portugal, Outpatient Tuberculosis Centres (OTBC) are responsible for the diagnosis, treatment, screening and prevention of tuberculosis (TB), and only severe or resistant cases are hospitalized. AIM: To understand how infection control norms and standards were applied and how these centres responded during the pandemic. METHOD: We sent an electronic questionnaire to all coordinators of OTBC. The questionnaire included questions on infection control during the COVID-19 pandemic and evaluation of the functioning of the OTBC in two periods: during the 1st National State of Emergency and after 1 year. RESULTS: Thirty-two responses were obtained (52.5%). The infection control norms were globally applied; diagnosis, treatment, and prevention were kept, and contact screening was only affected during the 1st State of Emergency. However, half of the respondents (53.1%) believed that there were diagnostic delays during the 1st State of Emergency, rising to 68.8% after 1 year. Only 31.3% performed Directly Observed Therapy (DOT) in all patients during the 1st State of Emergency, and 59.4% after 1 year. Half the inquiries expected an increase in TB incidence in the near future. CONCLUSION: The pandemic affected OTBC functioning, although the services were kept open; diagnostic delay and DOT appliance were the most affected.
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COVID-19 , Tuberculose , COVID-19/epidemiologia , Diagnóstico Tardio , Humanos , Pandemias , SARS-CoV-2 , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologiaRESUMO
COVID-19 vaccines are considered promising agents in the control of the pandemic. Although their safety was assessed in randomised clinical trials, severe adverse events (AEs) have been reported after large-scale administration. This study aims to evaluate thromboembolic AEs reported after vaccination in a real-world context and how they led to the interruption of vaccination campaigns. We also review the benefits and risks of the vaccines approved in the European Union and provide recommendations. A review of the literature was performed using Medline/PubMed electronic database as well as institutional and pharmacovigilance official reports. Our findings show that vaccine-induced prothrombotic immune thrombocytopenia has been suggested as a very rare AE associated with viral vector vaccines. Unusual thrombotic events combined with moderate-to-severe thrombocytopenia were reported mainly in women under 60 years of age. As safety signals emerged, Vaxzevria and Janssen´s COVID-19 vaccine campaigns have been paused while investigations proceed. On the other hand, the number of deep vein thrombosis and pulmonary embolism reports have not increased. Post-marketing surveillance indicated that mRNA vaccines are safe and should continue to be used. The thrombotic events report rate is not increased in people over 60 years. As they are at greater risk for COVID-19 complications and death, no vaccine restrictions are recommended in this group. Risk factors for vaccine-induced prothrombotic immune thrombocytopenia should be established so that evidence-based decisions can be made. Systematic monitoring of COVID-19 vaccine safety is essential to ensure that the benefits of vaccination outweigh the risks.
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COVID-19 , Vacinas , Vacinas contra COVID-19 , Feminino , Humanos , SARS-CoV-2 , Vacinação , Vacinas/efeitos adversosRESUMO
BACKGROUND: The COVID-19 outbreak and consequent physical distance measures implemented worldwide have caused significant stress, anxiety, and mental health implications among the general population. Unemployment, working from home, and day-to-day changes may lead to a greater risk of poor mental health outcomes. OBJECTIVE: This paper describes the protocol for a web-based cross-sectional study that aims to address the impact of the COVID-19 pandemic on mental health. METHODS: Individuals from the general population aged 18 years or more and living in Portugal were included in this study. Data collection took place between November 10, 2020, and February 10, 2021. An exponential, nondiscriminative, snowball sampling method was applied to recruit participants. A web-based survey was developed and shared on social media platforms (eg, Facebook, Instagram, Twitter, LinkedIn, and WhatsApp groups) and through e-mail lists for recruitment of the seeds. RESULTS: Data analysis will be performed in accordance with the different variables and outcomes of interest by using quantitative methods, qualitative methods, or mixed methods, as applicable. A total of 929 individuals had completed the web-based survey during the 3-month period; thus, our final sample comprised 929 participants. Results of the survey will be disseminated in national and international scientific journals in 2021-2022. CONCLUSIONS: We believe that the findings of this study will have broad implications for understanding the psychological impact of the COVID-19 pandemic on Portuguese residents, as well as aspects related to the informal economy. We also hope that the findings of this study are able to provide insights and guidelines for the Portuguese government to implement action. Finally, we expect this protocol to provide a roadmap for other countries and researchers that would like to implement a similar questionnaire considering the related conclusions. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/28071.
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In spite of the many studies examining alcohol consumption, recent reviews have indicated that binge drinking has not been extensively studied. Furthermore, it is becoming increasingly clear that sleep is associated with many physiological functions and to drug addictions. The present study aimed to evaluate the relationship between alcohol binge drinking and insomnia in college students of health sciences. All first-year health sciences students (n=286) were evaluated in a cross-sectional study. Envelopes containing the Insomnia Severity Index (ISI), the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST), and questions capturing sociodemographic data were distributed and collected in classes. It was found that most non-drinkers were female (70.6%), although there were no sex-related differences in the number of binge drinkers (more than 5 drinks on each occasion at least once a week), allowing statistical comparison. The Mann-Whitney U test indicated that the ISI scores were significantly greater in female than male binge drinkers (P=0.014). Moderate or severe insomnia was reported by 23% of the sample, with alcohol being the most frequently associated substance. A specialized intervention was suggested by ASSIST: brief for marijuana (19.2%) and tobacco (23.3%) use, and moderate (31.5%) or intensive (1.4%) for alcohol consumers. The data highlighted the need to pay attention to the habits of college students beyond obtaining scientific information. New data suggesting the influence of genetics on insomnia may be of importance when performing additional studies on the sex differences in alcohol binge drinking.
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Consumo Excessivo de Bebidas Alcoólicas , Distúrbios do Início e da Manutenção do Sono , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudantes , UniversidadesRESUMO
Infectious diseases, such as tuberculosis (TB) and the novel coronavirus (COVID-19) relate to environmental factors, understanding of which is essential to inform policy and practice and tackle them effectively. The review follows the conceptual framework offered by the World Health Organization Commission on Social Determinants of Health (defined as "all those material, psychological and behavioural circumstances linked to health and generically indicated as risk factors' in the conventional epidemiological language"). It describes the social factors behind TB and COVID-19, the commonalities between the two diseases, and what can be learned so far from the published best practices. The social determinants sustaining TB and COVID-19 underline the importance of prioritising health and allocating adequate financial and human resources to achieve universal health coverage and health-related social protection while addressing the needs of vulnerable populations. Rapid and effective measures against poverty and other major social determinants and sources of inequality are urgently needed to develop better health in the post-COVID-19 world.
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COVID-19 , Determinantes Sociais da Saúde , Tuberculose , Cultura , Status Econômico , Meio Ambiente , Insegurança Alimentar , Acessibilidade aos Serviços de Saúde , Habitação , Humanos , Desnutrição , SARS-CoV-2 , Classe SocialAssuntos
COVID-19 , Pandemias , Tuberculose , Humanos , Assistência Ambulatorial , Índia , Pacientes Ambulatoriais , SARS-CoV-2 , Tuberculose/terapiaRESUMO
In this work, we synthesized colloidal silica nanospheres with an average size of 400 nm through the modified Stöber method and successfully fabricated an ordered close-packed silica nanosphere monolayer onto ITO-coated glass substrates using a three-step spin-coating method. ITO films showed resistivity comparable to that of commercial ITO and the silica nanosphere monolayer-coated ITO/glass substrate exhibited good optical transmittance in the visible (550 nm) and near-infrared (900 nm) regions of 62% and 82%, respectively. The results suggest that this monolayer can be used in optoelectronic devices to enhance efficiency in photovoltaic cells.
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A series of 18 2-arylidene indan-1,3-dione derivatives was synthesized and tested against Daphnia magna to assess the environmental toxicity of these compounds. Aiming to investigate the toxicity mechanism for this series of compounds, a four-dimensional quantitative structure-activity analysis (4D-QSAR) was performed through the partial least square regression (PLS). The best PLS model was built with two factors and the selected field descriptors, of Coulomb (C) and Lennard-Jones (L) nature, describing 77.43% of variance and presenting the following statistics: r 2 = 0.89; SEC = 0.30; Q 2 = 0.81; SEV = 0.36. According to the literature, the bioactivity of α,ß-unsaturated ketones, a functionality present in the series of compounds under investigation, is related to the conjugated double bond with the carbonyl group. The presence of a positive Coulomb descriptor nearby the carbonyl moieties, obtained as a result of the regression model, indicates that these polar groups are also related to the toxicity on D. magna. From the PLS regression model, the toxicity EC50-48 h values increases with the positive Coulomb descriptor and diminishes with the negative Lennard-Jones descriptors. It could be concluded that the presence of small polar groups in the aromatic ring of the arylidene moiety tends to increase the toxicity, while bulkier apolar substituents lead to a decrease of the toxicity.
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Daphnia/efeitos dos fármacos , Indanos/toxicidade , Relação Quantitativa Estrutura-Atividade , Poluentes Químicos da Água/toxicidade , Animais , Indanos/química , Poluentes Químicos da Água/químicaRESUMO
Carbon-based tubular materials have sparked a great interest in future electronics and optoelectronics device applications. In this work, we computationally studied the mechanical properties of nanotubes generated from popgraphene (PopNTs). Popgraphene is a 2D carbon allotrope composed of 5-8-5 rings. We carried out fully atomistic reactive (ReaxFF) molecular dynamics for PopNTs of different chiralities ( n,0 and 0,n ) and/or diameters and at different temperatures (from 300 up to 1200â K). Results showed that the tubes are thermally stable (at least up to 1200â K). All tubes presented stress/strain curves with a quasi-linear behavior followed by an abrupt drop of stress values. Interestingly, armchair-like PopNTs ( 0,n ) can stand a higher strain load before fracturing when contrasted to the zigzag-like ones ( n,0 ). Moreover, it was obtained that Young's modulus (YMod ) (750-900â GPa) and ultimate strength (σUS ) (120-150â GPa) values are similar to the ones reported for conventional armchair and zigzag carbon nanotubes. YMod values obtained for PopNTs are not significantly temperature-dependent. While the σUS values for the 0,n showed a quasi-linear dependence with the temperature, the n,0 exhibited no clear trends.