COVID-19 transmission in U.S. transit buses: A scenario-based approach with agent-based simulation modeling (ABSM)

The transit bus environment is considered one of the primary sources of transmission of the COVID-19 (SARS-CoV-2) virus. Modeling disease transmission in public buses remains a challenge, especially with uncertainties in passenger boarding, alighting, and onboard movements. Although there are initial findings on the effectiveness of some of the mitigation policies (such as face-covering and ventilation), evidence is scarce on how these policies could affect the onboard transmission risk under a realistic bus setting considering different headways, boarding and alighting patterns, and seating capacity control. This study examines the specific policy regimes that transit agencies implemented during early phases of the COVID-19 pandemic inUSA, in which it brings crucial insights on combating current and future epidemics. We use an agent-based simulation model (ABSM) based on standard design characteristics for urban buses in USA and two different service frequency settings (10-min and 20-min headways). We find that wearing face-coverings (surgical masks) significantly reduces onboard transmission rates, from no mitigation rates of 85% in higher-frequency buses and 75% in lower-frequency buses to 12.5%. The most effective prevention outcome is the combination of KN-95 masks, open window policies, and half-capacity seating control during higher-frequency bus services, with an outcome of nearly 0% onboard infection rate. Our results advance understanding of COVID-19 risks in the urban bus environment and contribute to effective mitigation policy design, which is crucial to ensuring passenger safety. The findings of this study provide important policy implications for operational adjustment and safety protocols as transit agencies seek to plan for future emergencies.

Digital Media Effect on Diabetic Eye Care During COVID-19 pandemic

Purpose : To gauge the impact of healthcare technology in the management of diabetic retinopathy during the COVID-19 pandemic. Methods : The study was conducted at EyeCare Consultants of New Jersey's in their two locations in NJ, Woodland Park and Edison. Eye care professionals (ECPs-two ophthalmologists, one optometrist) surveyed 400 diabetic patients during the first year of the pandemic (March 2020- February 2021). The patients all received previous instructions with CheckedUp, a patient education digital platform utilizing audiovisual and touchscreen to further educate patients, during in-office visits. The 400 diabetic patients were divided equally into two groups. To ensure the adherence of dietary and behavioral modifications related to diabetes mellitus, Group 1 received traditional phone calls while Group 2 received video calls and supplementary education with CheckedUp. Both groups had a follow-up in person in September 2021. Surveys elicited responses to gauge consistency of HbA1C management. Results : Adherence was defined as HbA1C values which remained within a target value lower than or equal to their baseline and/or <7.0% as well as compliance with medications, dietary restrictions, regular physical activity and follow-up visits. The results found a significant difference between educating the patient with a phone call versus a video call and CheckedUp. At the next follow-up visit in person: Group 1 had an adherence of 48% (96 patients) and had several patients with HbA1C values exceeding the targeted value. Group 2 had an adherence of 69% (138 patients) and were more compliant with a healthier lifestyle. They also stated that their telehealth appointment with CheckedUp helped reinforce the importance of maintaining a normal HbA1C value. Conclusions : This study illustrates the ability of digital medicine platforms to supplement virtual and in-person consultations to manage diabetic retinopathy, especially during the pandemic. Compliance is an important matter in the management and preventing progression of diabetic retinopathy. Digital tools like CheckedUp assist with optimizing patient care in these unprecedented times.

An extensive study on Indian power sector affected by Covid-19 global pandemic

Corona Virus had a very undeterminable effect on the whole human race. The most important factor in today's age of artificial intelligence and the internet of things is energy, without which a successful generation's future cannot be imagined. Due to the outbreak of the COVID-19 pandemic, the energy sector had battled to stay afloat. The major weapon against the virus was a countrywide shutdown, which was a wise measure, but it also disrupted the economy's routine. According to Global energy review 2020, the countries observing complete lockdown experienced an average 25% decline in the energy demand per week, and the countries observing partial lockdown observed an average 18% decline. The challenges that the Indian power industry faced during the outbreak are examined in this article, and also a suggestion for developing countries to make their energy sectors more resilient to a once-in-a-generation calamity. The study reveals the factors which affect the working of a power sector of both renewable and non-renewable energy sectors which are climatic conditions, operational efficiency, capacity factor, load factor. As a result, we will look at how the crisis affected the factors and how the engineers dealt with the issues. © 2022 Author(s).

Effect of Double Mutation (L452R and E484Q) in RBD of Spike Protein on its Interaction with ACE2 Receptor Protein

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) caused coronavirus disease 2019 (COVID-19) pandemic has become a global health issue. Recently, the SARS-CoV-2 strain (B.1.617 double mutant variant) has raised alarms in India and other nations. B.1.617 variant was found to contain two key mutations (L452R and E484Q) in the RBD region of the spike protein. In this work, we have focussed on the effect of the double mutations in spike protein on its binding to the host cell receptor protein, angiotensin-converting enzyme 2 (ACE2). From the molecular dynamics simulation, we observed that the L452R and E484Q double mutant (DM) in spike protein utilizes unique strategies to achieve stable binding to ACE2 compared to the spike protein's wild type (WT). Using MM-GBSA/MM-PBSA algorithms, we found that the binding affinity between spike protein-containing DM and ACE2 is high (GBTOT =-47.09 kcal mol-1, PBTOT=-19.93 kcal mol-1) in comparison with spike protein WT and ACE2 (GBTOT =-31.79 kcal mol-1, PBTOT=-6.33 kcal mol-1). Stable binding of spike protein to ACE2 is essential for virus entry. They should understand interactions between them while designing drugs and treatment modalities to target or disrupt this interface. © 2022 by the authors.

A rare case of esophageal granular cell tumor in a young patient presenting with heartburn

Introduction: Granular cell tumors (GCTs) of the esophagus are rare and benign neoplasms of neural cell origin. The lesions are often incidentally identified during upper endoscopic evaluation for other indications. We report a case of esophageal GCT in a young patient who presented with heartburn. Case Description/Methods: A 29-year-old white woman with a history of bulimia nervosa, gastroesophageal reflux disease, and chronic diarrhea following a recent COVID-19 infection presented to the clinic with heartburn and regurgitation that had been ongoing for years. She recently switched her omeprazole to famotidine to prepare for conception, which made her symptoms worse. Her physical examination and laboratory investigations were unremarkable. Esophagogastroduodenoscopy showed a single 6 mm yellowish, firm, submucosal nodule in the distal esophagus (Fig. 1A) and chronic gastritis. The nodule was biopsied with cold forceps and proved to be a granular cell tumor (Fig. 1B). The granular cell tumor cells were negative for pan-cytokeratin and positive for S100 (Fig 1C). They were negative for CD45 and Synaptophysin by immunohistochemistry staining. Biopsy of the distal esophagus also confirmed a short segment of Barrett's esophagus without dysplasia. Gastric body and antrum biopsy showed mild chronic gastritis negative for Helicobacter pylori. She was scheduled for an endoscopic ultrasound followed by possible endoscopic mucosal resection. Discussion: Even though esophageal GCTs are benign incidental findings, they have malignant potential (1-4%). Mortality is related to the size, growth, and invasiveness of the tumor. Indications for endoscopic or surgical resection are large size ≥ 1 cm, rapid growth, high suspicion of malignancy, transmural infiltration, and persistent symptoms. Endoscopic resection techniques include endoscopic mucosal resection and submucosal tunnel endoscopic resection. The later is more preferred in lesions < 3 cm. One study reported no recurrence of esophageal GCTs after resection in 14 cases at a median of 4-year follow-up.