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This paper derived fractional derivatives with Atangana-Baleanu, Atangana-Toufik scheme and fractal fractional Atangana-Baleanu sense for the COVID-19 model. These are advanced techniques that provide effective results to analyze the COVID-19 outbreak. Fixed point theory is used to derive the existence and uniqueness of the fractional-order model COVID-19 model. We also proved the property of boundedness and positivity for the fractional-order model. The Atangana-Baleanu technique and Fractal fractional operator are used with the Sumudu transform to find reliable results for fractional order COVID-19 Model. The generalized Mittag-Leffler law is also used to construct the solution with the different fractional operators. Numerical simulations are performed for the developed scheme in the range of fractional order values to explain the effects of COVID-19 at different fractional values and justify the theoretical outcomes, which will be helpful to understand the outbreak of COVID-19 and for control strategies. © 2022 the Author(s), licensee AIMS Press.
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Flipped learning to date has generally been implemented within a blended classroom. However, the growing number of fully online courses and the existence of Covid-19 have shown the need to try using flipped learning in a fully online class. This paper aimed to explore student achievement and perceptions in an online flipped grammar class. A paired-sample t-test showed a significant difference between students' pre-test and post-test scores with a medium effect size after attending the online flipped course for one month. The interview and questionnaire data revealed students' overall positive perceptions toward the introduction of flipped learning within the course. Students mentioned that the flipped approach made the course more interactive and provided them opportunities to ask questions to the teacher with an immediate answer. They also expressed their positive attitude towards the use of different learning platforms (e.g., LMS, Zoom) and modes (synchronous and asynchronous) that could ease their learning experience within the course. Nevertheless, students recommended that the virtual meeting via Zoom needs to be limited in time duration. © 2021 Authors. All Rights Reserved.
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SESSION TITLE: Medical Student/Resident Disorders of the Mediastinum Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: In March, 2020 the World Health Organization (“WHO”) declared SARS-CoV-2 as a global pandemic. SARS-CoV-2 viral infection has been noted to present a variety of symptoms including anosmia (loss of sense of smell), dyspnea, cough, fever, diarrhea and acute respiratory failure. Spontaneous pneumomediastinum is a rare complication with viral pneumonia. We here present one of the two cases with this finding. CASE PRESENTATION: 63-years-old male presented with fever, chills, and progressive shortness of breath over the past week. Patient was previously diagnosed with corona virus disease with reverse transcriptase RNA PCR test. Past medical history was significant for diabetes, hypertension and hyperlipidemia. On presentation, patient was hypoxic (SaO2 84%). Physical examination revealed reduced breath sounds bilaterally and soft-tissue crepitus in bilateral clavicle area. Laboratory test results showed elevated C-reactive protein concentration, leukocytosis, and lymphopenia. Chest Computed Tomography (CT) showed diffuse lower neck/chest wall subcutaneous emphysema with associated diffuse pneumomediastinum and bilateral ground-glass airspace infiltrates (Figure 1,2,3). Patient was started on anti-infective therapy with vancomycin, piperacillin/tazobactam, and azithromycin, and placed on nasal cannula at 4 liter/minute. On day four of admission, patient developed multi-organ failure requiring mechanical ventilation and vasopressor support. Later on day twelve, patient expired due to cardiopulmonary arrest. DISCUSSION: Pneumomediastinum is defined as the presence of free air in the mediastinum with an incidence of 1 in every 25,000 cases in ages between 5-34 years, predominantly found in males. It may be spontaneous from a predisposing factor or due to secondary causes. SARS-CoV-2 is a new addition to secondary pulmonary causes, being reported recently in literature. The pathophysiology of spontaneous pneumomediastinum is explained due to pressure gradient difference between alveoli and lung interstitial tissue. SARS-CoV-2 infects type I and II pneumocytes, disrupting alveolar membrane integrity leading to alveolar rupture and leakage of air into interstitial tissue, as well as severe hypoxemia increasing respiratory effort. Associated clinical symptoms of pneumomediastinum are varying, including dyspnea, although a portion of patient are asymptomatic. Pneumomediastinum is typically identified through chest x-ray with management being primary conservative. CONCLUSIONS: Spontaneous pneumomediastinum in association with SARS-CoV-2 is a serious condition and merits early recognition. Despite early diagnosis and optimal management, the mortality was 100% in our two patients of Covid-19 associated mediastinum. Reference #1: Wang J, Su X, Zhang T, Zheng C. Spontaneous Pneumomediastinum: A Probable Unusual Complication of Coronavirus Disease 2019 (COVID-19) Pneumonia. Korean J Radiol. 2020;21(5):627-628. doi:10.3348/kjr.2020.0281 Reference #2: Dionísio P, Martins L, Moreira S, et al. Spontaneous pneumomediastinum: experience in 18 patients during the last 12 years. J Bras Pneumol. 2017;43(2):101-105. doi:10.1590/S1806-37562016000000052 Reference #3: Kolani S, Nawfal H, Haloua M, et al. Spontaneous pneumomediastinum occurring in the SARS-COV-2 infection [published online ahead of print, 2020 May 11]. IDCases. 2020;21:e00806. doi:10.1016/j.idcr.2020.e00806 DISCLOSURES: No relevant relationships by Darakhshan Ahmad, source=Web Response No relevant relationships by Marium Ghani, source=Web Response No relevant relationships by Parvez Mir, source=Web Response No relevant relationships by Judy Pham, source=Web Response No relevant relationships by Yariana Rodriguez-Ortiz, source=Web Response No relevant relationships by Phanthira Tamsukhin, source=Web Response