Machine Learning Insights into Regional Dynamics and Prevalence of COVID-19 Variants in US Health and Human Services Regions (preprint)

Background The COVID-19 pandemic arising from the emergence of SARS-CoV-2 in late 2019 has led to global devastation with millions of lives lost by January 2024. Despite the WHO's declaration of the end of the global health emergency in May 2023, the virus persists, propelled by mutations. Variants continue to challenge vaccination efforts, underscoring the necessity for ongoing vigilance. This study aimed at contributing to a more data-driven approach to pandemic management by employing random forest regression to analyze regional variant prevalence.Methods This study utilized data from various sources including National COVID Cohort Collaborative database, Bureau of Transportation Statistics, World Weather Online, EPA, and US Census. Key variables include pollution, weather, travel patterns, and demographics. Preprocessing steps involved merging and normalization of datasets. Training data spanned from January 2021 to February 2023. The Random Forest Regressor was chosen for its accuracy in modeling. To prevent data leakage, time series splits were employed. Model performance was evaluated using metrics such as MSE and R-squared.Results The Alpha variant was predominant in the Southeast, with less than 80% share even at its peak. Delta surged initially in Kansas City and maintained dominance there for over 5 months. Omicron subvariant BA.5 spread nationwide, becoming predominant across all Health and Human Services regions simultaneously, with New York seeing the earliest and fastest decline in its share. Variant XBB.1.5 concentrated more in the Northeast, but limited data hindered full analysis. Using RF regressor, key features affecting spread patterns were identified, with high predictive accuracy. Each variant showed specific environmental correlations; for instance, Alpha with air quality index and temperature, Delta with ozone density, BA.5 with UV index, and XBB.1.5 with location, land area, and income. Correlation analysis further highlighted variant-specific associations.Conclusions This research provides a comprehensive analysis of the regional distribution of COVID-19 variants, offering critical insights for devising targeted public health strategies. By utilizing machine learning, the study uncovers the complex factors contributing to variant spread and reveals how specific factors contribute to variant prevalence, offering insights crucial for pandemic management.

Single-cell transcriptome landscape of circulating CD4+ T cell populations in human autoimmune diseases (preprint)

CD4+ T cells are a key mediator of various autoimmune diseases; however, how they contribute to disease development remains obscure primarily because of their cellular heterogeneity. Here, we evaluated CD4+ T cell subpopulations by decomposition-based transcriptome characterization together with canonical clustering strategies. This approach identified 12 independent transcriptional gene programs governing whole CD4+ T cell heterogeneity, which can explain the ambiguity of canonical clustering. In addition, we performed a meta-analysis using public single-cell data sets of over 1.8M peripheral CD4+ T cells from 953 individuals by projecting cells onto the reference and cataloged cell frequency and qualitative alterations of the populations in 20 diseases. The analyses revealed that the 12 transcriptional programs were useful in characterizing each autoimmune disease and predicting its clinical status. Moreover, genetic variants associated with autoimmune diseases showed disease-specific enrichment within the 12 gene programs. The results collectively provide a landscape of single-cell transcriptomes of CD4+ T cell subpopulations involved in autoimmune disease.

Result of SARS-CoV-2 nucleic acid test for aerosol in a designated COVID-19 hospital

OBJECTIVE: To collect aerosol from isolation wards of a designated COVID-19 hospital and conduct the nucleic acid test so as to provide scientific basis for prevention and control of COVID-19. METHODS: The air aerosol specimens were collected from layout sites in the isolation wards of the hospital by using bioaerosol collector, and the COVID-19 nucleic acid test was carried out for all of the specimens by using fluorescent polymerase chain reaction(PCR) and digital PCR. RESULTS: A total of 86 aerosol samples were collected, all of which were tested negative for the fluorescent PCR, the result of the digital PCR test showed that 14 air aerosol samples were tested positive for COVID-19 nucleic acid, with the detection rate 16.28%. The toilets of the patients and taking-off area of protective supplies of healthcare workers were the major places where the specimens were tested positive. The positive rate of nucleic acid test was significantly higher in in intensive care units than in common wards, however, there was no significant difference in the positive rate of nucleic acid among the aerosol specimens in different wards(?-2=7.871, P=0.248);there was no significant difference in the positive rate of nucleic acid of aerosol between the patients with CT value more than 30 and the patients with CT value no more than 30(?-2=0.232, P=0.630). CONCLUSION: There are still viral nucleic acids in the air aerosol of the isolation wards during the middle and late disease course of the COVID-19 patients, but the copy number of novel coronavirus is not large in the specimens. The detection rate of the viral nucleic acid is high in the aerosol of the wards that are crowed and poorly ventilated and are associated with the cases. It is necessary for the health care workers to take good care of themselves, keep the environment well ventilated and do a good job in environmental cleaning and disinfection and air purification.

Applying Importance–Satisfaction Model to Evaluate Customer Satisfaction: An Empirical Study of Foodpanda

Because of improving mobile platforms and faster 4G speed, the annual growth of mobile devices has exceeded 50%, and many catering enterprises have integrated services to make ordering and delivery more convenient for smartphone users. Thus, user satisfaction with new online food-delivery platforms and services needs to be explored and evaluated. Using an Importance–Satisfaction Model (I–S Model), this study applied 12 service elements obtained from previous studies and an in-depth discussion of experts and scholars to evaluate user satisfaction towards Foodpanda, the first online food delivery service provider in Taiwan. Questionnaires were distributed from June to July 2020 and 256 samples were collected. This study found that eight items fell within the “Excellent Area”, one within the “Improvement Area” and three within the “Careless Area”.

Optimization of multi-V filter design for airliner environmental control system using an empirical model

With the wide use of multi-V filters in aircraft cabins, it is necessary to establish a pressure drop prediction and optimization model for multi-V HEPA cabin filters. Based on approximate solution of the Navier-Stokes equation and with the aid of CFD simulations, we developed an empirical equation for the overall pressure drop across a multi-V HEPA cabin filter. The measured pressure drop across the filter was used to verify the accuracy of the empirical equation. The equation was then used to develop two optimized design procedures for multi-V HEPA cabin filters with low pressure drop and high filtration efficiency. The structural parameters of the filters obtained by the two design procedures were consistent and very close to the actual parameters. Compared with CFD, this empirical equation is easier to use and involves only a short calculation time. The empirical equation and optimized design procedures are useful for filter design.

A Single-Center Retrospective and Descriptive Study of Hepatobiliary and Pancreatic Surgical Oncology during the COVID-19 Epidemic (preprint)

Objective: In the battle against COVID-19, most medical resources in China have been directed to infected patients in Wuhan. Thus, patients with hepatobiliary pancreatic tumors who are not suffering from COVID-19 are often not given timely and effective anti-cancer treatments. In this study, we aimed to describe clinical characteristics, treatment, and outcomes of patients with hepatobiliary and pancreatic oncology from our department, which retained normal working during the COVID-19 epidemic. We also sought to formulate a set of standardized hospitalization and treatment processes.Methods: A retrospective and descriptive study was conducted involving patients hospitalized from February 1, 2020, to February 29, 2020 (Return to work after the Spring Festival), at our Department of Hepatobiliary and Pancreatic Surgical Oncology. Results: The study included 92 patients from 12 provinces in the north of China who underwent surgical resection at our Department of Hepatobiliary and Pancreatic Surgical Oncology during the COVID-19 epidemic. Robotic surgery was performed on 82% (75/92) of patients, while the rest underwent laparoscopic (2/92) and open surgery (15/92). Eighty-six patients had malignant tumor, and six had emergency benign diseases. Only five patients had severe pancreatic fistula, and three had biliary fistula after operation. Conclusions: The standardized hospitalization and treatment processes described in this study could prevent cross-infection of patients and still ensure timely treatment of patients with hepatobiliary and pancreatic cancers. These study findings will guide the management of surgical oncology departments and treatment of patients with hepatobiliary and pancreatic oncology during serious epidemics.

Early antiviral therapy of abidor combined with lopinavir/ritonavir and re-combinant interferonα-2b in patients with novel coronavirus pneumonia in Zhejiang: A multicenter and prospective study / 中华临床感染病杂志

Objective@#Comparing the benefit of Abidor, lopinavir/ritonavir and recombinant interferon α-2b triple combination antiviral therapy and lopinavir/ritonavir and interferon dual combination antiviral therapy to hospitalized novel coronavirus pneumonia 2019 in Zhejiang province.@*Methods@#A multi-center prospective study was carried out to compare the effect of triple combination antiviral therapy with dual combination antiviral therapy in 15 medical institutions of Zhejiang Province. All patients were treated with recombinant interferon α-2b (5 million U, 2 times/d) aerosol inhalation. 196 patients were treated with abidol (200 mg, 3 times/d) + lopinavir / ritonavir (2 tablets, 1 time/12 h) as the triple combination antiviral treatment group. 41 patients were treated with lopinavir / ritonavir (2 tablets, 1 time/12 h) as the dual combination antiviral treatment group. The patients who received triple combination antiviral therapy were divided into three groups: within 48 hours, 3-5 days and > 5 days after the symptom onset. To explore the therapeutic effects of triple combination antiviral drugs and dual combination antiviral drugs, as well as triple combination antiviral drugs with different antiviral initiate time. SPSS17.0 software was used to analyze the data.@*Results@#The time of virus nucleic acid turning negative was (12.2 ± 4.7) days in the triple combination antiviral drug group, which was shorter than that in the dual combination antiviral drug group [(15.0 ± 5.0) days] (t = 6.159, P < 0.01 ). The length of hospital stay [12 (9, 17) d] in the triple combination antiviral drug group was also shorter than that in the dual combination antiviral drug group [15 (10, 18) d] (H = 2.073, P < 0.05). Comparing the antiviral treatment which was started within 48 hours, 3-5 days and > 5 days after the symptom onset of triple combination antiviral drug group, the time from the symptom onset to the negative of viral shedding was 13 (10,16.8), 17 (13,22) and 21 (18-24) days respectively (Z = 32.983, P < 0.01), and the time from antiviral therapy to the negative of viral shedding was (11.8±3.9) , (13.5±5.1) and (11.2±4.3) d. The differences among the three groups were statistically significant (Z=32.983 and 6.722, P<0.01 or<0.05).@*Conclusions@#The triple combination antiviral therapy of Abidor, Lopinavir/Litonavir and recombinant interferon α-2b showed shorter viral shedding time and hospitalization time compared with the dual combination antiviral therapy. The earlier the time to initiate triple antiviral treatment, the shorter the time of virus shedding.

Risk factors and clinical features of deterioration in COVID-19 patients in Zhejiang, China: a single- centre, retrospective study (preprint)

BackgroundSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection swept through Wuhan and spread across China and overseas beginning in December 2019. To identify predictors associated with disease progression, we evaluated clinical risk factors for exacerbation of SARS-CoV-2 infection.MethodsA retrospective analysis was used for PCR-confirmed COVID-19 (coronavirus disease 2019)-diagnosed hospitalized cases between January 19, 2020, and February 19, 2020, in Zhejiang, China. We systematically analysed the clinical characteristics of the patients and predictors of clinical deterioration.ResultsOne hundred patients with COVID-19, with a median age of 54 years, were included. Among them, 49 patients (49%) had severe and critical disease. Age ([36-58] vs [51-70], P=0.0001); sex (49% vs 77.6%, P=0.0031); Body Mass Index (BMI ) ([21.53-25.51] vs [23.28-27.01], P=0.0339); hypertension (17.6% vs 57.1%, P<0.0001); IL-6 ([6.42-30.46] vs [16.2-81.71], P=0.0001); IL-10 ([2.16-5.82] vs [4.35-9.63], P<0.0001); T lymphocyte count ([305- 1178] vs [167.5-440], P=0.0001); B lymphocyte count ([91-213] vs [54.5-163.5], P=0.0001); white blood cell count ([3.9-7.6] vs [5.5-13.6], P=0.0002); D2 dimer ([172-836] vs [408-953], P=0.005), PCT ([0.03-0.07] vs [0.04-0.15], P=0.0039); CRP ([3.8-27.9] vs [17.3-58.9], P<0.0001); AST ([16, 29] vs [18, 42], P=0.0484); artificial liver therapy (2% vs 16.3%, P=0.0148); and glucocorticoid therapy (64.7% vs 98%, P<0.0001) were associated with the severity of the disease. Age and weight were independent risk factors for disease severity.ConclusionDeterioration among COVID-19-infected patients occurred rapidly after hospital admission. In our cohort, we found that multiple factors were associated with the severity of COVID19. Early detection and monitoring of these indicators may reduce the progression of the disease. Removing these factors may halt the progression of the disease. In addition, Oxygen support, early treatment with low doses of glucocorticoids and liver therapy, when necessary, may help reduce mortality in critically ill patients.

Retrospective study of low-to-moderate dose glucocorticoids on viral clearance in patients with novel coronavirus pneumonia / 中华临床感染病杂志

Objective@#To study the effect of low-to-moderate dose glucocorticoid therapy on viral clearance time in patients with COVID-19.@*Methods@#A total of 72 patients diagnosed with COVID-19 from January 19 to February 17, 2020 at the First Affiliated Hospital, School of Medicine, Zhejiang University were recruited. All patients received oral abidol and/or combined lopinavir/ritonavir, darunavir antiviral, and symptomatic supportive care. Among them, 51 patients received methylprednisolone (0.75-1.50 mg·kg-1·d-1) (glucocorticoid treatment group), and 21 patients who did not use glucocorticoid were the control group. The time of stable virologic conversion insputumand the time of radiologic recovery in lungsince onset were compared between the two groups and among the normal patients.The Kruskal-Wallis test or Fisher exact test was used to compare the difference between groups.@*Results@#The median ages of the glucocorticoid group and the control group were 52 [interquartile range (IQR):45, 62] years and 46 (IQR: 32, 56)years, and the differences were significant (P<0.05). The clinical conditions at hospital admission were different between the two groups (P<0.01). There were 52.0% critical ill patients in the glucocorticoid treatment group, compared to that of 71.4% normal patients in the control group. The median times from the onset tostable virologic conversion to negative in the two groups were 15 (IQR:13,20) days and 14 (IQR:12,20) days (P>0.05), and the difference was no statistically significant. The median times from onset to radiologic recovery were 13 (IQR: 11,15) days and 13 (IQR:12,17) days in the two groups, and there was no difference (P>0.05). In ordinary patients, the median timesfrom the onset tostable virologic conversion insputum were no difference (P>0.05), with 13 (IQR:11,18) days in the glucocorticoid group and 13 (IQR:12,15) days in the control group; The median times from onset to radiologic recovery in lungwere also no difference (P>0.05), with 12 (IQR: 10,15)days in the glucocorticoid group and 13 (IQR: 12,17) days inthe control group.@*Conclusions@#Low-to-moderate glucocorticoid treatment has no effect on the time of virus clearance in patients with different clinical types of COVID-19. The glucocorticoid is not recommended since no effectiveness on accelerating the improvement of radiologic recovery in lung has been observed.