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Purpose: Drawing on the concept of community of practice, the purpose of this study was to explore Brazilian physical education teachers' experiences of nurturing a community of practice online during the COVID-19 pandemic. Method: This was an action research project, and the participants were 13 high school physical education teachers (one of them acted as teacher-facilitator), one critical friend, and one meta-critical friend. Data sources included teachers' online meetings, critical friend conversations, interviews, and the facilitator's reflexive journal. Results: Inductive analysis resulted in four themes: finding emotional and pedagogical support, building a teachers-only space, creating an online group dynamic, and negotiating to research their own practice. The findings are discussed in relation to the characteristics of community of practices and online continuing professional development. Conclusion: Key aspects for future online collaborative continuing professional development are highlighted: (a) teachers-only;(b) by teachers, for teachers;and (c) combination of tools.
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This work presents the development, test, and validation of a system that gathers and analyses data from optical sensors to monitor the air quality of indoor environments to help prevent Severe Acute Respiratory Syndromes (SARS). © Optica Publishing Group 2022 The Authors.
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Em 2020, presenciamos o surto mundial da COVID-19, doenca infecciosa provocada pelo coronavirus (SARS-Cov-2). As apresentacoes hematologicas e bioquimicas sao importantes para a abordagem clinica e tem impacto sobre o esquema terapeutico. Os achados disponiveis na literatura estabelecem claramente a participacao do laboratorio de hematologia como importante parceiro na triagem e manejo dos pacientes afetados. Neste contexto, este estudo teve como objetivo descrever os perfis hematologico e bioquimico dos pacientes portadores das formas moderadas e graves da infeccao, admitidos em um hospital de referencia. Avaliamos dados de exames de 235 pacientes, do momento da admissao no complexo hospitalar terciario (aprovacao CEP-CAEE sob ndegree 36812820.3.0000.0068) de marco a junho/2020. O diagnostico do virus SARS-Cov-2 foi feito atraves do exame RT-PCR, de acordo com os criterios da OMS. Parametros hematologicos foram obtidos atraves dos hemogramas realizados na rotina laboratorial, por analisadores automatizados, microscopia automatizada e convencional, quando necessarias. Foram avaliados os Dimero-D, TP, TTPA, igualmente obtidos da rotina laboratorial automatizada. A dosagem de Proteina C reativa foi realizada utilizando o metodo automatizado Imunoturbidimetrico. As informacoes foram obtidas pelo Sistema de Gestao e Informacao Hospitalar. A interpretacao dos resultados foi baseada nos intervalos de referencia utilizados pelo laboratorio. Foi utilizada estatistica descritiva para calcular frequencia e porcentagem e os dados apresentados em tabelas e graficos. Tecnicas estatisticas utilizadas: Analise Descritiva Unidimensional;Analise Descritiva Multidimensional;Testes de Hipoteses Parametricas;Associacao e Dependencia de Dados Qualitativos;Analise de Dados Categorizados. Encontramos a distribuicao por sexo: 138 homens (58,72%) e 97 mulheres (41,28%). A faixa etaria teve variacao de 6 meses a 93 anos com media de 55,8 anos. Os principais achados foram concordantes com a literatura: linfocitopenia em 198 (84,2%), seguido por neutrofilia em 141 (60%), plaquetopenia em 60 (25,5%) e leucocitose em 58 (24,6%). O Dimero-D mostrou-se elevado em 208 pacientes (88,5%). O numero absoluto de neutrofilos e de linfocitos, alem de valores para Dimero-D mostraram maior relacao com a idade do paciente no momento da admissao e o desfecho do caso. Em relacao ao PCR, encontramos apenas 6 pacientes dentro da faixa normal (<5 mg/L). Analisando os valores aumentados, verificamos que pacientes com valores ate 50 mg/L apresentaram taxa de alta de 76%, enquanto pacientes que apresentaram taxas acima de 50 mg/L, mostraram que a taxa de altas diminui para 61%. Considerando a variavel Dimero-D, estima-se que a chance de obito quando este e maior que 2 x vezes o normal, e 3,1 vezes a chance de obito quando Dimero-D e ate 2 x vezes o normal;interpretacao semelhante pode ser feita para as variaveis idade, leucocitos totais, linfocitos, PCR e segmentados. Os valores-p dos testes qui-quadrado de Pearson confirmam evidencia de associacao entre o desfecho (obito ou alta) com as variaveis idade, Dimero-D e de neutrofilos. Na faixa de idade superior a 59 anos, Dimero-D acima de 2 vezes o normal e baixo percentual de linfocitos aumentam consideravelmente a chance de obito. Embora os dados descritos devam ser validados com estudos adicionais, foram evidenciadas caracteristicas do perfil hematologico de pacientes com COVID-19, uteis a pratica laboratorial e a abordagem clinica. Copyright © 2022
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Background: Covid-19 is associated with an increased risk of pulmonary embolism (PE) therefore, should the cut off d-dimer value be adjusted for these patients? Material(s) and Method(s): Retrospective and observational study to understand if there is a d-dimer cut-off that could guide clinics to perform a thoracic computed tomography angiography (CTA) in patients with covid-19. The population was covid-19 patients admitted to covid-19 dedicated wards of a University Hospital Centre for one year. Result(s) and Conclusion(s): 725 (52%) patients with covid-19 had a d-dimer value dosed during the first 5 days of the disease. Those, 63 (9%) did a CTA with a diagnosis of 16 (25%) PE. Gender was equally represented, median age was 70 years (ID=3.49) and the majority (94%) survived. Thirteen (81%) patients with PE had a d-dimer value above 2500 ng/mL (OR=9.244, 95% CI 2.248-9.837), with 7 (54%) with values over 10000 ng/mL, but in 3 (9%) it was under 1500 ng/mL. Seventy-three (63%) of patients with a d-dimer over 1500 ng/mL did not had a thoracic CTA performed. In our population PE was not a frequent outcome. The results are influenced by the low number of thoracic CTA performed because, even tough the cut-off d-dimer value used at our hospital to perform a thoracic CTA to exclude PE is 1500 ng/mL, most patients with that d-dimer value did not take the exam and so PE could not be excluded. Although in most PE cases the d-dimer value was above 2500 ng/mL, the results of our study cannot verify if that is a better cut-off value.
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Background: The association between atrial fibrillation (AF) and prognosis has been studied in non-COVID-19 patients, but few studies reflect the reality of critically ill COVID-19 patients admitted to a general intensive care unit (ICU). Purpose: This study sought to investigate the relationship between previous and new-onset AF in COVID-19 patients admitted to an ICU and prognosis. Methods: We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19 and followed them for a median period of 7 months. Patients admitted due to trauma or emergent surgery were excluded from the analysis. Three groups were identified: without AF (G1), with prior history of AF (G2), and with new-onset AF (G3). Groups were compared, with special interest regarding ICU mortality, duration of mechanical ventilation, length of hospitalization, major adverse cardiac events (MACE), and re-hospitalization. MACE was defined as all-cause ICU mortality, new-onset heart failure, acute coronary syndrome, ventricular arrhythmias, pulmonary embolism, myocarditis, and stroke (ischemic or hemorrhagic). Results: A total of 297 patients was included in the analysis: without AF (248 patients, 83.5%), with prior history of AF (15 patients, 5.1%), and with new-onset AF (34 patients, 11.4%). Median age was 62 (IQR 17) years, and most patients were male (198 patients, 66.7%).Patients with a prior history of AF were older [median (IQR), G1 60 (16), G2 71 (12), G3 67 (15) years, p=0.001], were more likely to have a history of coronary artery disease (G1 4.9%, G2 26.7%, G3 11.8%, p=0.002), and history of heart failure (G1 6.5%, G2 33.3%, G3 17.6%, p<0.001). Patients with new-onset AF had a longer duration of mechanical ventilation [median (IQR), G1 9 (13), G2 11 (16), G3 18 (12) days, p<0.001), longer ICU length of stay [median (IQR), G1 12 (10), G2 13 (12), G3 19 (15), p=0.001], higher ICU mortality rate (G1 27.0%, G2 33.3%, G3 58.8%, p=0.001), and higher rate of MACE (G1 31.9%, G2 33.3%, G3 70.6%, p<0.001), compared to the other groups. There were no differences regarding sex distribution, other baseline comorbidities, need for invasive mechanical ventilation, vasopressor use, and re-hospitalization rates among groups. Most AF patients were treated with beta-blockers (39.6%) and amiodarone (77.1%), but only 68.8% of patients received anticoagulation (G2 92.9%, G3 58.8%), which may reflect that physicians underestimate the prognosis of new-onset AF.In multivariate analysis, new-onset AF (OR 3.07, 95% CI 1.42–6.67, p=0.005) and older age (OR 1.07, 95% CI 1.04–1.09, p<0.001) remained independent predictors of ICU mortality. Main results are presented in Table 1. Kaplan-Meier survival curves are presented in Figure 1. Conclusion(s): This study shows that critically ill COVID-19 patients with AF present a worse prognosis compared to patients without AF, and new-onset AF is an independent predictor of ICU mortality and MACE. Funding Acknowledgement: Type of funding sources: None.Table 1. Main resultsFigure 1
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Background: Critically ill patients hospitalized with COVID-19 are at high risk of developing major adverse cardiac events (MACE). Purpose: This study aimed to identify independent predictors of MACE after intensive care unit (ICU) admission which could be used to identify high-risk patients who may benefit from preventive strategies. Methods: We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19 and followed them for a median period of 7 months. Patients admitted due to trauma or emergent surgery were excluded. Logistic regression analysis was performed to evaluate which clinical characteristics predicted MACE. MACE was defined as all-cause ICU mortality, new-onset heart failure, acute coronary syndrome, ventricular arrythmias, pulmonary embolism, myocarditis, and stroke (ischemic or hemorrhagic). Results: A total of 297 patients was included in the analysis. Median age was 62 (IQR 17) years, and most patients were male (198 patients, 66.7%). From a total of 297 patients, 108 (36.4%) developed at least one MACE: ICU all-cause mortality (92 patients, 31.0%), new-onset heart failure (27 patients, 9.1%), acute coronary syndrome (7 patients, 2.4%), ventricular arrythmias (7 patients, 2.4%), pulmonary embolism (13 patients, 4.4%), myocarditis (4 patients, 1.3%), and stroke (5 patients, 1.7%).Univariate logistic regression analysis showed that the clinical variables associated with MACE were male sex, older age, APACHE II score, SAPS II score, hypertension, hyperlipidemia, known coronary artery disease, heart failure, new-onset atrial fibrillation, need for invasive mechanical ventilation, duration of mechanical ventilation, and vasopressor use. In multivariate logistic regression analysis, we found that the MACE's independent predictors were older age, higher APACHE II score, and new-onset atrial fibrillation. Main results are presented in Table 1. Conclusion(s): Among critically ill COVID-19 patients, older age, higher APACHE II score, and new-onset atrial fibrillation independently predicted MACE. Funding Acknowledgement: Type of funding sources: None.Table 1. Main results
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Funding Acknowledgements Type of funding sources: None. Background/Introduction Among patients with COVID-19, there is a high prevalence of cardiovascular disease and myocardial injury from the infection, especially in critically ill patients. Purpose This study sought to investigate the relationship between elevated admission high-sensitive troponin I in COVID-19 patients admitted to an intensive care unit (ICU) and prognosis. Methods We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19, with a median follow-up of 10 months. Patients who were diagnosed with acute coronary syndrome, either died or were discharged within 48 hours of admission, and who did not have a cardiac troponin measurement in the first 48 hours, were excluded. Two groups were identified, with normal troponin and with elevated troponin. Groups were compared, with special interest regarding in-hospital mortality, duration of mechanical ventilation, in-hospital diagnosis of heart failure, and length of hospitalization. Global mortality (in-hospital and during follow up) and re-hospitalization were compared. To compare survival, a Kaplan-Meier curve with log rank test was performed. Results From a total of 219 patients, after applying the exclusion criteria, 100 patients were included in the analysis, mean age was 62.9 ±12.5 years, and 74% were male. Troponin was normal in 77% of patients and elevated in 23%. Median troponin was 11 (IQR=26) ng/L (reference range <34 ng/L). Patients with elevated troponin were older (66.5 ±12.0 vs 61.6 ±12.5 years, p=0.036). Gender, comorbidities, vasopressor use, and APACHE II score were similar among groups. Patients with elevated troponin presented a higher ICU mortality (16.9% vs 47.8%, p=0.002) and higher global mortality (22.1% vs 47.8%, p=0.016). Re-hospitalization rates, ICU length of stay and duration of mechanical ventilation were similar among groups. In multivariate analysis, after adjustment for age and APACHE II score, an elevated troponin remained an independent predictor of ICU mortality (OR=3.40, 95% CI 1.08-10.4, p=0.036), but not an independent predictor of global mortality (OR=2.75, 95% CI 0.86-8.80, p=0.087). Kaplan-Meier analysis (Figures 1 and 2) showed that patients with elevated troponin had higher ICU (p=0.008) and global mortality (p=0.008) when compared to patients with normal admission troponin. Conclusion(s) The present study shows that elevated high-sensitive cardiac troponin I at admission predicts ICU and global mortality in critically ill COVID-19 patients. Cardiac troponin is as easy-to-use tool that may help to identify patients who benefit from tighter monitoring both during hospitalization and after discharge.
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Funding Acknowledgements Type of funding sources: None. Background/Introduction It is now well known that patients with COVID-19 have a high prevalence of cardiovascular disease. COVID-19 is also associated with a substantial degree of cardiovascular involvement. However, the impact of cardiovascular disease (CVD) and cardiovascular risk factors on the natural history of COVID-19 is much less characterized. Purpose To characterize the prognostic impact of CVD and cardiovascular risk factors in COVID-19 patients admitted to an Intensive Care Unit (ICU). Methods We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19, with a median follow-up of 10 months. Patients who either died or were discharged in the first 48 hours of admission were excluded. Three groups were identified: (1) established CVD – presence of either heart failure, coronary artery disease and/or peripheral artery disease; (2) at higher risk of CVD – arterial hypertension, dyslipidemia, diabetes mellitus and/or smoking, in the absence of established CVD; and (3) at lower risk of CVD – i.e. none of the above. Groups were compared, with special interest regarding in-hospital mortality, duration of mechanical ventilation, length of hospitalization. Global mortality (in-hospital and during follow up), and re-hospitalization were also compared. To compare survival, a Kaplan-Meier and multivariate Cox regression analysis were performed. Results Overall, 219 patients were identified, mean age was 62.1 ±11.9 years, 67.1% were male, 71 (32.4%) died in the ICU, 78 (35.6%) died during follow-up, and 14 (6.4%) were re-hospitalized. 30 patients (13.7%) had established CVD, 144 (65.8%) were at higher risk of CVD, and 45 (20.5%) were at lower risk of CVD. Patients with established CVD were older than patients at higher risk of CVD, and both were older than patients at lower risk (68.0 ±8.4 vs 62.0 ±11.3 vs 56.0 ±13.0 years, p <0.001). ICU mortality was 56.7%, 30.6%, and 22.2% for patients with established CVD, at higher risk of CVD, and at lower risk of CVD, respectively (p = 0.005). Re-hospitalization rate, ICU length of stay, and duration of mechanical ventilation were similar among groups. Patients with established CVD were at significantly higher risk of ICU mortality (HR 2.42, 95% CI 1.08-5.46, p = 0.033), and higher risk of global mortality (HR 2.16, 95% CI 1.03-4.52, p = 0.042), compared to patients at higher and lower risk of CVD;in patients at higher and lower risk of CVD, ICU and global mortality was similar. In multivariate Cox regression, after adjusting for age and risk scores, established CVD was not an independent predictor of mortality. Kaplan-Meier survival curves are presented in figures 1 and 2. Conclusion(s) Almost 80% of patients admitted to an ICU with COVID-19 had established or were at higher risk of CVD. Patients with established CVD have a higher risk of death, although its presence is not an independent predictor of death.
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Background: The COVID-19 pandemic has had a dramatic impact on clinical practice, amounting to more emergency department and intensive care unit (ICU) admissions. Due to their frequent multiple comorbidities, management in the ICU is challenging. Early studies suggest that cardiac injury is frequent in hospitalized patients with COVID-19, and it is plausible that these patients have a higher risk of cardiac dysrhythmias. Purpose: To determine the prevalence of dysrhythmias in ICU patients with COVID-19 pneumonia, identify major predictors and determine the impact on in-hospital mortality. Methods: A retrospective study of 98 consecutive patients with COVID-19 Pneumonia admitted to the ICU of a tertiary hospital in 2020. The main outcome was dysrhythmias (including significant bradycardia, high/slow ventricular rate or new-onset atrial fibrillation (AF) or atrial flutter, other supraventricular tachycardias, ventricular tachycardia and ventricular fibrillation). Significant bradycardia was defined as heart rate lower than 40 or need of treatment. Sociodemographic variables and clinical data were retrieved for each patient, severity scores at admission (Apache II, SOFA and SAPS II), number of days on mechanical ventilation or high-flow oxygen and placement on Venovenous Extracorporeal Membrane Oxygenation (ECMO) or prone position were recorded. Statistical comparison was made between groups, including logistic regression adjusting for confounding variables. Results: The most frequent arrhythmia was significant sinus bradycardia (28, 28.5%) followed by high ventricular rate AF (14, 14.2%). Patients who had dysrhythmias were older (66.24 ± 10.13 vs 60.85 ± 12.69 years, p 0.024), more severe (SAPS II score 42.55 ± 11.08 vs 35.98 ± 11.26, p 0.006), had more atrial fibrillation (AF) (p 0.022), had higher maximum C-reactive protein (mCRP) (6.56 ± 2.68 vs 6.24 vs 2.86, p 0.009), were mechanically ventilated for a longer time (15.64 ± 13.18 vs 8.92 ± 8.85 days, p 0.004), had longer intubation time (14.52 ± 9.39 vs 8.70 ± 8.21 days, p 0.002) and had higher usage of dexamethasone (p 0.042) and prone position (p 0.016). When adjusted for confounding variables, prone was the most significant predictor (OR 2.800;95% CI 1.203-6.516) followed by use of dexamethasone (OR 2.484;95% CI 1.020-6.050). Days intubated, days on mechanical ventilation, age, mCRP and SAPS II on admission were also predictors of dysrhythmia. Regarding mortality, patients with arrhythmic events had a tendency for greater in-hospital death (OR 2.440;95% CI 0.950-6.310;p 0.065). Conclusions: COVID-19 ICU patients are a subset of patients at risk of cardiac arrhythmias. Use of prone position was the main contributor to these events, but clinical history, severity and treatment may also play an important role. Efforts must be made to optimize ventilatory support and treatment in order to reduce the risk of dysrhythmias. (Figure Presented).
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Background: The COVID-19 pandemic has shifted tremendously the paradigm of hospital care and treatment of cardiovascular (CV) patients. According to most recent evidence, due to its multisystemic impact, COVID-19 may lead to an increased risk of cardiac arrhythmias with subsequently increased morbimortality. Purpose: Determine the prevalence of tachyarrhythmias in patients admitted with COVID-19, possible predictors and impact on in-hospital mortality. Methods: A retrospective study of 3475 consecutive patients with COVID-19 pneumonia admitted to our hospital between February 2020 and November 2021 were included. The main outcome was tachyarrhythmias (high ventricular rate (HVR) or new-onset atrial fibrillation (AF), HVR or new-onset atrial flutter (AFL), other supraventricular tachycardias (SVT), ventricular tachycardia (VT) and ventricular fibrillation (VF)). Secondary outcome was in-hospital mortality. Sociodemographic variables and clinical data were recorded. Statistical comparison was made between groups, including logistic regression to determine odds ratios (OR). Results: A total of 215 patients presented HVR AF (6.31%), 79 of which with new-onset AF (36.74%). 8 patients had HVR AFL (0.23%), 5 VT (0.15%), 4 VF (0.12%) and only 3 patients had a SVT identified (0.09%). Patients with tachyarrhythmias were significantly older (77. 74 ± 11.25 68.94 ± 17.51 years, p <0.001) and had more hypertension (p 0.034), heart failure (HF) (p <0.001), severe valvular heart disease (VHD) (p 0.007), coronary artery disease (CAD) (p 0.031), chronic kidney disease (CKD) (p 0.048) and paroxysmal AF (if previously diagnosed (p 0.001). There were no significant differences regarding gender, dyslipidemia, diabetes, cerebrovascular disease and obstructive sleep apnoea (OSA). Patients with HF had the highest risk of tachyarrhythmia (OR 3.539;95% CI 2.666-4.698;p <0.001), followed by severe VHD (OR 1.990;95% CI 1.192-3.365;p 0.009) and CAD (OR 1.575;95% CI 1.040-2.386;p 0.032). Older patients or patients with hypertension or CKD were also at an increased risk. Also of note, patients previously diagnosed with paroxysmal AF were more likely to have episodes of HVR AF than the ones with persistent or permanent AF (OR 1.819;95% CI 1.272-2.602;p 0.001) Regarding the secondary outcome, patients with tachyarrhythmias during hospital stay had an odd almost 3 times higher of death (OR 2.820;95% CI 2.151-3.695;p <0.001). Conclusions: Tachyarrhythmias is a common complication in COVID-19 patients during hospital stay that is significantly linked to higher in-hospital mortality. Patients presenting with high CV disease burden are at particularly significant risk and should be carefully managed. Odds-ratio of tachyarrhythmias (Figure Presented).
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The current article has the main goal of debate the dynamics in the spread of Covid-19 based on the mobility of patients in the urban area of São Luís, Maranhão State. The time frame include the first 100 days of the pandemic, in the urban area of São Luís. The acknowledged data consists of ICU (intensive care units) spaces and the viral evolution during this time frame. The main data sources are the “Datasus” and the Maranhão State of health department. The characteristic suggests that the concentration of medical-hospital equipments in few cities, specially in Imperatriz, is considered a big bottle neck related to the fight against the pandemic Sars-CoV-2, since it requires more people mobility from centers with less health service offers to the ones with more health service offers, resulting into bigger contamination areas. Thereby the disease dissemination works in an hierarchical way in the urban area of the city, information that is not always clear in the data presented by the epidemiologic report. © 2021, Universidade Federal de Goias. All rights reserved.
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The Amazonas was one of the most heavily affected Brazilian states by the COVID-19 epidemic. Despite a large number of infected people, particularly during the second wave associated with the spread of the Variant of Concern (VOC) Gamma (lineage P.1), SARS-CoV-2 continues to circulate in the Amazonas. To understand how SARS-CoV-2 persisted in a human population with a high immunity barrier, we generated 1,188 SARS-CoV-2 whole-genome sequences from individuals diagnosed in the Amazonas state from 1st January to 6th July 2021, of which 38 were vaccine breakthrough infections. Our study reveals a sharp increase in the relative prevalence of Gamma plus (P.1+) variants, designated Pango Lineages P.1.3 to P.1.6, harboring two types of additional Spike changes: deletions in the N-terminal (NTD) domain (particularly Delta 144 or Delta 41-144) associated with resistance to anti-NTD neutralizing antibodies or mutations at the S1/S2 junction (N679K or P681H) that probably enhance the binding affinity to the furin cleavage site, as suggested by our molecular dynamics simulations. As lineages P.1.4 (S:N679K) and P.1.6 (S:P681H) expanded (Re > 1) from March to July 2021, the lineage P.1 declined (Re < 1) and the median Ct value of SARS-CoV-2 positive cases in Amazonas significantly decreases. Still, we did not find an increased incidence of P.1 variants among breakthrough cases of fully vaccinated patients (71%) in comparison to unvaccinated individuals (93%). This evidence supports that the ongoing endemic transmission of SARS-CoV-2 in the Amazonas is driven by the spread of new local Gamma/P.1 sublineages that are more transmissible, although not more efficient to evade vaccine-elicited immunity than the parental VOC. Finally, as SARS-CoV-2 continues to spread in human populations with a declining density of susceptible hosts, the risk of selecting more infectious variants or antibody evasion mutations is expected to increase. IMPORTANCE The continuous evolution of SARS-CoV-2 is an expected phenomenon that will continue to happen due to the high number of cases worldwide. The present study analyzed how a Variant of Concern (VOC) could still circulate in a population hardly affected by two COVID-19 waves and with vaccination in progress. Our results showed that the answer behind that was a new generation of Gamma-like viruses, which emerged locally carrying mutations that made it more transmissible and more capable of spreading, partially evading prior immunity triggered by natural infections or vaccines. With thousands of new cases daily, the current pandemics scenario suggests that SARS-CoV-2 will continue to evolve and efforts to reduce the number of infected subjects, including global equitable access to COVID-19 vaccines, are mandatory. Thus, until the end of pandemics, the SARS-CoV-2 genomic surveillance will be an essential tool to better understand the drivers of the viral evolutionary process.
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We propose a new concept and architectural design for a double hybrid tailsitter unmanned aerial vehicle with vertical takeoff and landing capability. Basically, it consists of a modified flying wing with a single combustion powertrain set and a multirotor with 2 powertrain sets with electric motors. To this end, we have designed, built, and tested a prototype that spends less energy on vertical taking off and landing and also on horizontal flight, for maximizing flight endurance and distance.With electric propellers fixed at the leading wing edge, the tailsitter has two standard surfaces for elevation control and two vertical stabilizers that are used to give the necessary direction on vertical takeoff and landing. Experiments and results show the versatility of our hybrid tailsitter for operations in a restricted field. We performed several tests starting with the aircraft on the ground in vertical positioning. These tests include executing vertical takeoffs and landing, transitions from vertical to horizontal flight modes and transitions back from horizontal to vertical flight modes, and hovering, which were carried out successfully. Transition fourth and back from combustion to multirotor modes are inherent to some of those flight mode transitions, which have been performed smoothly.We also performed tests (in bench) to estimate the flight endurance. Final autonomous flight adjustments were not performed due to the Covid-19 pandemic caused by SARS-CoV-2. To this end the proposed and currently built prototype has proven to be functional as an effective hybrid UAV system. Author
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Advanced fitting of ordinary differential equations models to experimental results is presented within the context of different academic levels of students and diverse research fields. In many areas, the analysis of experimental results cannot be restricted to cases where particular solutions of the models' differential equations, valid only for specific limit conditions, apply. In those cases, analytical mathematical equations are not available and a complete description of the systems extends beyond the numerical minimization of statistical estimators, like the chi-square, because it requires solving numerically the models' differential equations. Dedicated fitting procedures that involve the interdependent processes of solving the ordinary differential equations and fitting the numerical solutions to the experimental results are required to obtain the best fitting sets of parameters with consistent physical meaning. A simple, but powerful, web-based ordinary differential equations solver and fitter is presented, and used to analyse both the complete motion of a rigid pendulum and the dynamics of a viral infection.
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This article has as main goal to discuss the Covid-19 spread due to the mobility of the patients over the urban network in the city of Imperatriz, in Maranhao State. The analyzed time frame refers to the first 100 days of the pandemic, emphasizing the urban network of the Imperatriz city space. The examined data of the ICU, hospital beds and respirators in the State, also the data about the viral evolution in this period. The main data source are the Datasus and the Maranhao State health offil ce. The studied characteristics suggest that the medical-hospital equipment concentration in few cities of the State, especially in Imperatiz, is an expressive bottleneck when fighting the Sars-CoV-2 pandemic, due to the necessity of mobilization of people from the smaller centers with less health services to the ones with more hospital beds, resulting in more spread areas. Therefore, the spread of the disease happens in a graduated way in the urban network of the city, and this data is not always evident in the epidemiologic reports.
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Background: COVID-19 was first considered a pandemic on the 11th of March of 2020 by the World Health Organization. Its impact comprised not only the direct consequences of the disease but a decrease in the follow-up and interventions of patients with cardiovascular (CV) disease. In Portugal and the World, the consequences of this complex paradigm shift on emergent pacemaker implantation rates during and after this pandemic is largely unknown. Purpose: We sought to analyse the impact of COVID-19 pandemic on emergent pacemaker implantation rate and patient profile in a tertiary hospital during the first Portuguese lockdown and subsequent post-lockdown period. Methods: We retrospectively reviewed the clinical profile of patients who had pacemakers implanted in our hospital in an urgent/emergent setting from March 18, 2020 to May 17, 2020 (lockdown) and May 19 to July 17, 2020 (post-lockdown). This data was then directly compared to the homologous periods from the year before (H1 and H2, respectively). Results: A total of 180 patients submitted to emergent pacemaker implantation were included. The cohort was comprised of 29 patients who had a pacemaker implanted during lockdown, 60 post-lockdown, 38 in H1 (+31% vs lockdown) and 53 in H2. Average age and gender proportion were similar for all groups. When comparing lockdown and post-lockdown periods, the number of cases significantly increased in the second period (+106.9%) and there was a tendency for a higher number of temporary pacemaker use (3.4% vs 16.7%;p=0.076). Patients admitted during lockdown were 7.57 times more likely to present with hypotension/shock (odds ratio (OR) 7.57;p=0.013). Regarding lockdown and its homologous 2019 period, there was a decrease in the number of patients admitted (-23.7%). Again, there was a higher tendency for hypotension on presentation during lockdown (p=0.054). In comparison to its homologous 2019 period, post-lockdown saw a slight increase in the number of patients (+13.2%) and more patients presented with bradycardia (16.7% vs 3.8%;p=0.026). Also of note, no patients were admitted to the emergency department during lockdown for anomalies detected on ambulatory tests (Holter, electrocardiogram or implanted loop recorder). Conclusion: During lockdown, clinical presentation was generally more severe, with a greater number of patients presenting with hypotension/ shock. In addition, there appears to be a lockdown effect on emergent bradyarrhtmias admissions in the post-lockdown period with a profound impact: higher admission rates and more severe presentations including a higher need of temporary pacemaker. Patients with symptoms suggestive of bradyarrhythmias should be advised to present promptly regardless of the pandemic. (Figure Presented).
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The coronavirus pandemic (Sars-CoV-2) has impacted many aspects of human life and specially the international civil aviation sector. Thus, this research investigates: the existence and extent of a human duty attributed to airline operators to promote health in international commercial passenger flights, regarding the prevention and containment of communicable diseases, in periods of pandemic and return to normality. Therefore, guided by a deductive approach and in the light of the International Theory of Human Duties, the article analyzed: norms of Public International Law about aviation, health and sanitation;as well as judgments from different courts on the subject. Thus, by interpreting the term accident, the possibility of assigning such human duty to airlines was found, whose extension should cover the flight, boarding and disembarking of passengers. In addition, there was a brief analysis of the costs of such a duty, seeking to present alternatives for its costing in society, however, given its relevance, this topic should be analyzed in greater depth in future research. Thus, this article contributes towards, within the scope of international civil aviation, establishing paths aimed at resolving sanitary crises of an unusual magnitude, from the perspective of human duties. © 2021 Centro Universitario de Brasilia. All rights reserved.