ABSTRACT
The global tourism industry is struggling to recover from the COVID-19 pandemic. During the COVID-19 pandemic, daily tourism forecasting is more critical than ever before in supporting decisions and planning. Considering the changes in tourist psyche and behaviour caused by COVID-19, this study attempts to investigate whether the statistical modelling methods can work reliably under the new normal when travel restrictions are eased or lifted. To this end, we first compare the predictivity of daily tourism demand data before and during COVID-19, and observe heterogeneous impacts across different geographical scales. Then an improved multivariate & multiscale decomposition-ensemble framework is proposed to forecast daily tourism demand. The empirical study indicates the superiority and practicability of the proposed framework before and during COVID-19. Finally, we call for more research on the comparability of tourism demand forecasting.
ABSTRACT
Surface longwave downward radiation (LWDR) is a key factor affecting the surface energy balance. The daily LWDR and the diurnal variations of LWDR are of great significance for studies of climate change and surface processes. How to obtain LWDR at an averaged temporal scale from instantaneous LWDR is one of the longstanding problems in the field of radiation budget from remote sensing. In this paper, two temporal upscaling methods are introduced, namely, a method based on the diurnal variations of LWDR (diurnal variation based, DVB) and a method based on random forest regression (RFR). The results reveal that: (1) The DVB method has a global hourly and daily LWDR root-mean-square error (RMSE) of less than 21 W/m2 and 15 W/m2, respectively, and the RMSE of the daily LWDR based on RFR is less than 7 W/m2;(2) When compared with four existing statistical interpolation methods, the DVB method can not only ensure the accuracy, but also can overcome the problem of missing samples and/or an abnormal samples during upscaling;(3) Except for directly predict daily LWDR, the DVB methods can also obtain more accurate LWDR diurnal variations such as hourly, half-hourly etc. The RFR method enables high-efficiency and accurate estimation of daily averaged LWDR from instantaneous measurements. Compared with existing methods and products, the proposed methods are not only efficient, but also have a superior applicability and reliable accuracy. The proposed strategies provide new ideas for the community in estimating LWDR at continuous temporal scales from remotely sensed measurements.
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To understand the influence of coronavirus disease control policies on changes in characteristics of particulate matter smaller than 2.5 μm (PM2.5), concentrations of various PM2.5 components in Jinan city before and after implementation of the epidemic control measures during the 2020 Spring Festival were studied using online monitoring data. Standardized multiple linear regression was used to analyze the contribution of meteorological factors to the variations in concentrations of PM2.5 components. After the epidemic control measures were implemented, the concentrations of PM2.5 components in the area decreased significantly, and the rate at which the daily average concentration was exceeded decreased by 24.8%. The concentrations of all PM2.5 components decreased to various degrees, with those of trace elements (TE), elemental carbon (EC), and nitrate (NO3−) having decreased significantly by 50.3%, 46.8%, and 31.5%, respectively. In terms of component proportions, those of TE and EC decreased after the epidemic control measures were initiated whereas those of ammonium (NH4+), organic matter (OM), sulfate (SO4 2− ), and mineral dust increased;the proportion of NO3 − changed slightly, and the total proportion of secondary ions SO4 2−, NO3−, and NH4 + increased by 14.3%. Comparison of the proportions of PM2.5 components showed that after the epidemic control measures were implemented, the proportions of NO3 − and EC in PM2.5 that cause a light pollution level decreased whereas those of OM, SO4 2−, and NH4 + increased. This indicated that people traveled less, motor vehicle emissions decreased, work at construction sites stopped, and NO3 − proportion was greatly reduced while epidemic control measures were in place. However, afterward, decrease in concentrations of PM2.5 components and increase in secondary transformation of volatile organic compounds led to an increase in OM concentration. Compared with those before the epidemic control measures were implemented, the NO2/SO2 and NO3– /SO4 2− ratios fell significantly, and their average values decreased by 30.0% and 14.0%, respectively, indicating that the contribution of mobile sources (e.g., automobile exhaust) to pollution had decreased during the epidemic control period. Under the influence of the control measures, the OC concentration also decreased for excellent, good, and mild pollution levels;however, the secondary organic carbon concentration increased, indicating that secondary conversions did not decrease under the epidemic control conditions. Standardized multiple linear regression analyses of meteorological factors showed that changes in the height of the boundary layer contributed the most (46.5%) to changes in concentrations of PM2.5 components before the epidemic control measures were implemented;afterward, humidity was the primary factor governing the increase in these concentrations. © 2022, The Science Press. All rights reserved.
ABSTRACT
The COVID-19 lockdown has opened a unique window for investigating aerosol formation and evolution with controlled anthropogenic emissions in urban areas. Here, variations of PM2.5 chemical compositions, gaseous pollutants, meteorological conditions, and secondary organic aerosol (SOA) molecular tracers were monitored during three stages at an urban site (Pudong) and a suburban site (Qingpu) in Shanghai, which were defined as pre-COVID lockdown (PL), during COVID lockdown (DL), and after COVID lockdown (AL) in 2020. Abundances of pollutants during the same periods back in 2019 were also analyzed for a more comprehensive intercomparison and evaluation of the impact of the 2020 COVID-19 lockdown on regional air quality. With the sudden cessation of anthropogenic activities during the lockdown, significant reductions in PM2.5 were observed compared to both PL in 2020 (32% in Pudong and 36% in Qingpu) and the DL period back in 2019 (31% in Pudong and 35% in Qingpu), which was accompanied by the significantly reduced PM2.5 components (29-44% and 14-44% reductions in sulfate, nitrate, ammonium, organic carbon, and elemental carbon for Pudong and Qingpu, respectively). In particular, with the reduced secondary inorganic aerosol (SIA), the time series of SOA molecular tracers also underwent significant reduction that was characteristic to the lockdown. Amid the uncontrolled biogenic emissions and even slightly enhanced atmospheric oxidation capacity during the 2020 DL period, controlling anthropogenic emissions exhibits synergistic effects on the reduction of SIA and SOA, which could be further attributed to the changes in the aerosol aqueous-phase environment, such as aerosol liquid water content (ALWC), ionic strength, sulfate content, and particulate NH4+. Based on thermodynamic modeling, greatly reduced ALWC was observed during 2020 DL, which can prevent the partitioning of oxygenated organics into the condensed phase as well as the aqueous-phase formation of SOA. Higher ionic strength in 2020 DL may have a "salting-out" effect on gas- particle partitioning of oxygenated organics. The reduced SOA during 2020 DL at both sites can generally be reflected by the predicted heterogeneous reaction kinetics (gamma) of the isoprene SOA formation pathway. Overall, our study showed a synergistic effect in suppressing SIA and SOA formation upon the reduction of anthropogenic emissions during the COVID-19 lockdown, which shed light on the importance of controlling anthropogenic emissions in regulating secondary aerosol formation in typical urban areas of East China.
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The porcine epidemic diarrhea virus (PEDV) is a major pathogen of swine enteric diseases. Various etiology and serological methods have been employed for PEDV detection, but most of their applications are limited to lab-oratories. To extend PEDV detection to on-site applications, we design a homogeneous fluorescence resonance energy transfer (FRET)-based enzyme-linked immunosorbent assay (ELISA). Both donor and acceptor fluores-cence microspheres modified PEDV antibodies can be linked only to the occurrence of PEDV antigen, thus generating FRET signals, which can be collected by our designed portable FRET immunoassay station (FRETIS). Verified by standard samples, FRET immunoassay reached high sensitivity with a detection limit as TCID50 (median tissue culture infective dose) of 10/mL, which is 10 times more sensitive than colloidal gold test strips;and verified by clinical samples, it was also proved with high accuracy, good selectivity, and repeatability. More importantly, FRET immunoassay could detect PEDV in a 96-well plate in 35 min with only one step of incubation without any further washing steps using field-portable devices and field-operable procedures, well supporting on -site applications. Considering these advantages, this reported FRET immunoassay provides a promising way for multi-sample on-site PEDV detection and can be potentially used in the swine industry.
ABSTRACT
Meditation and mindfulness are practices that can reduce psychological stress and stress-related health problems during times of crisis such as the current global pandemic caused by COVID-19. Promoting well-being at all ages is essential to sustainable development, and in this study, we proposed a neuro and biofeedback meditation virtual reality application and heart rate band called Gaia VR to make meditation fun, measurable, and personalized. This system could also potentially reduce the stress people have been experiencing in the pandemic. By implementing data such as heart rate variability and Alpha brainwaves, users can get feedback on their daily stress level and interact with the virtual reality environment through their meditation based on how relaxed they are through the process. © 2022 IEEE.
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This study focuses on developing an effective online teaching strategy to improve students' cognition engagement and application ability by applying design thinking and case readings on current economic issues for private university students in Taiwan during the COVID-19 pandemic. The teaching method combines design thinking and the reading comprehension process by the two principles of divergence and convergence. The design thinking method provides stepwise guidance for building understanding and analyzing competence on current economic issues. The reading comprehension process strengthens students' reading skills and learning capability. This combination increases student engagement and concentration in economic case readings during online learning. The research participants comprised 189 first-year students studying economics courses. After implementing the innovative teaching strategies, the results show that the more students are involved in frequent readings, the better are their economics semester grade. The findings revealed that their post-quiz scores improved significantly, and the semester grade increased by 3.44 points. Increasing the reading engagement on current economic issues cases also affected the learning outcomes for absentees. Using design thinking to introduce case reading comprehension, empathy has been suggested as an essential factor affecting the effectiveness of reading learning. This theoretical model can offer directional insights and guidance on developing an effective strategy in online economics education. © 2022 Conscientia Beam. All Rights Reserved.
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The global hospital's capacity can gradually decline, especially after the outbreak of the COVID-19, and thus traditional medical methods can no longer bear a large number of patients. At present, most hospitals rely on doctors and nursing staff to diagnose and treat patients. This not only increases the burden on doctors and nursing staff but also greatly reduces the burden on health care quality. In order to obtain better health care quality, automation is one of the important factors in solving medical quality problems. We are conducting automated introduction research for the ultrasonic scanner. Robotic arms are used to replace doctors for consultations by adding jelly and injection buttons to the robotic arm. In terms of the contact between the end of the robotic arm and the human body, we introduced the force sensor and the depth camera into the robotic arm. With the force sensor and the depth camera feedback data, we perceive the feedback of the ultrasonic scanner and the human body contact force. The results show that our design can greatly increase the amount of hospital's capacity and reduce the burden on doctors. © 2021 IEEE.
ABSTRACT
Introduction: There is limited literature on the cardiovascular manifestations of post-acute sequelae of SARS-CoV-2 infection (PASC). Methods: All consecutive adult patients presenting to the cardiology clinic at Yale-New Haven Hospital since July 2020, with positive COVID-19 serologic testing, were included. Results: Of 71 patients, average age was 46 years (range 19-74 years), 44 (62%) were female. 51 (72%) were White. 19 (27%) patients were hospitalized for COVID-19 (Table). Comorbidities included Hypertension (27%), hyperlipidemia (25%), diabetes (24%), and obesity (30%). On average, patients presented four months after COVID-19 diagnosis. The most common symptoms at presentation were dyspnea (45%, almost all exertional), palpitations (49%), and chest pain/pressure (49%). Patients also had memory impairment (20%), fatigue (39%), and headache (14%). There was no significant difference in cardiopulmonary symptoms (dyspnea, palpitations, and chest pain/pressure) by hospitalization status (p=0.70). TTE was abnormal in 13 of 62 patients and cardiac MRI was abnormal in 10 of 17 patients. Women experienced more cardiopulmonary symptoms (p=0.02) than men. Hospitalized patients were more likely to have ventricular dysfunction than non-hospitalized patients, although there were no significant differences in abnormal MRI findings (p=0.38). Diagnostic yield included: nonischemic cardiomyopathy (6%);new ischemia (3%);coronary vasospasm (1%);new atrial fibrillation (1%);possible myocarditis based on symptoms, MRI LGE (8%) or inflammation (3%). Two people met POTS criteria;majority of patients had evidence of sinus tachycardia and exertional fatigue consistent with orthostatic intolerance and deconditioning. Conclusions: In this cohort of patients referred to a cardiology clinic for PASC, cardiopulmonary symptoms did not differ by hospitalization status, however women were more likely to experience these symptoms than men.
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BACKGROUND. COVID-19 is a prothrombotic disease, characterized by endotheliopathy, hypercoagulability, and thromboembolic complications. We hypothesized that the pathogenesis of thromboembolism associated with COVID-19 might differ from thromboembolism in patients without COVID-19. In this study, we sought to evaluate the proteomic signatures of plasma from patients with venous thromboembolism with and without COVID-19. METHODS. Between December 17, 2020 and February 25, 2021 blood was collected from 48 hospitalized patients. Of these 24 had a confirmed diagnosis of COVID-19 infection (COVID+) and radiologic confirmation of arterial or venous thromboembolism (TE+);17 had COVID-19 infection with absence of arterial thrombosis clinically and absence of venous thromboembolism on lower extremity Doppler ultrasound or chest CT angiography (COVID+/TE-), while 7 were arterial or venous thromboembolism in the absence of COVID-19 (COVID-/TE+). Blood was collected in sodium citrate tubes and centrifuged at 4000 rpm for 20 minutes, with resulting plasma supernatant used for protein profiling performed at Eve Technologies (Calgary, Alberta, Canada). Institutional Review Board approval was obtained for this study. Statistical analysis was performed using GraphPad Prism (v9.1, GraphPad Software, San Diego, CA) and R (v4, R Core Team). P values <0.05 were considered statistically significant. A heatmap was generated using Heatmapper (heatmapper.ca) to represent the concentrations of proteins. RESULTS. The median age was 63 years;overall 25 (52%) were men (13 [54%] among COVID+/TE+, 11 [65%] among COVID+/TE-, and 1 [14%] among COVID-/TE+). In COVID-19 patients who developed thromboembolic events, several proteins associated with inflammation, complement activation, and hemostasis were present at higher levels than in non-COVID-19 patients who developed thromboembolic events (Fig. 1). These included complement factors C2 and C5a, pentraxin-3 (PTX-3), lipocalin-2 (LCN2), resistin (RETN), platelet endothelial cell adhesion molecule-1 (Pecam1), serum amyloid A (SAA), and tissue factor (TF). The heatmap indicates relative protein levels detected in each subject (columns) for proteins (rows) that had statistically significant differences between groups (Fig. 2). Heatmap revealed relatively lower levels of all proteins in patients with thromboembolism without COVID-19 and relatively higher levels of proteins in patients with COVID-19, and especially in ICU patients with COVID-19 and thromboembolism. CONCLUSIONS. Thromboembolic complications in patients with COVID-19 are associated with increased levels of various proteins involved in complement activation and immunothrombotic cascades, compared to thrombotic events in the absence of COVID-19. Activation of the classical complement pathway as evidenced by a relative increase in complement factor C2 may lead to increased TF activation, reflecting more substantial endothelial damage in COVID-19 patients. Higher levels of Pecam1, SAA, LCN2, and RETN all point to increased endotheliopathy, inflammation, and tissue damage in COVID-19 compared to non-COVID-19 thrombosis. These findings may offer insights into novel therapeutic strategies to treat immunothrombotic complications of COVID-19. [Formula presented] Disclosures: No relevant conflicts of interest to declare.
ABSTRACT
Baicalin, a flavonoid compound extracted from the rhizome of Scutellar iae Baicalensis, plays a vital role in improving liver function after injury, reducing liver disease and treating primary liver cancer, which is also the first SARS-CoV-2 3CLpro virus inhibitor according to the latest research data published in Bio-Rxiv. Therefore, constructing a simple and highly sensitive analytical method for the determination of baicalin is of great significance for the clinical and pharmacy settings. Herein, for the first time, carbon dots are explored for baicalin detection. Using biomass waste grape peels as the organic carbon source, nitrogen-doped fluorescent carbon dots (PT-NCDs) were fabricated, which were synthesized perfectly by a simple, environmentally friendly and one-step solid-phase thermal method without adding any other organic or acid/base reagents. Based on the synergistic effect of photo-induced electron transfer and dynamic quenching, a quenched fluorescence sensor for the determination of baicalin with a good linear range of 0.1-20 mu M and a satisfactory detection limit of 43.8 nM was constructed, which successfully quantified trace amount of baicalin in baicalin capsules, human serum and urine samples. The results indicate that PT-CDs are expected to become potential sensing materials for the real-time monitoring of baicalin in organisms, which is very important for our health. (C) 2021 Elsevier Ltd. All rights reserved.
ABSTRACT
The main method to diagnose COVID-19 is a nucleic acid test from a throat swab. Routine manual collection methods expose medical personnel to high-risk environment, which has a high risk of cross-infection. A throat swab sampling robot was developed to take the place of medical staff. The automatic segmentation of M-region in the pharyngeal swab image, which plays a core guiding role when the robot takes a throat swab sample. Aiming at the problem of discontinuous or fuzzy boundary in M-region of oral cavity, the segmentation accuracy is affected. An improved U-Net model is proposed and a new multi-scale feature fusion module with channel attention mechanism is presented. The ability of adaptive learning is enhanced and the segmentation precision of M-region with discontinuous or fuzzy edges is increased. Oral images of 45 volunteers were collected for training and testing. Experimental results showed that the model could accurately segment M-region in pharyngeal swab images, and compared with other segmentation networks, it has better indexes of segmentation precision.
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Owing to the convergence of multiple cultures coupled with the unprecedented rapid development in the decades since the late 1990s, the value creation and innovation logic of Asia-Pacific business models (BMs) has been constantly altered by cultural heterogeneity and thus, have evolved into a more complex and diverse landscape relative to Western developed-economy BMs. Given that relevant issues remain under-researched, the main purpose of our collection is to fill this gap. We provide new insights into identifying, exploring and rationalizing the indigenous innovation ecosystems and unorthodox value-creating logic of BMs emerging from the Greater China territory. Moreover, whereas the COVID-19 crisis has fundamentally changed the way people do business along with the lockdowns followed by some forms of de-globalization;it is expected to see a new wave of BM evolution. We, thus, outline three promising and nascent pathways for future efforts departing from a cultural view to explore the value logic of BMs and BM innovation within the Asia-Pacific region in the post-COVID-19 era: (1) the role of culture in BM innovation;(2) new ways of creating the knowledge and managing knowledge iceberg phenomenon and (3) using the 'Bottom of Pyramid' approach to BM innovation for incorporating social goals into value creation logic.
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Objective: To discuss the feasibility and practice of online examination for undergraduate pathological anatomy course during the COVID-19 epidemic. Methods: We used online examination system of superstar at Fudan University Online Education Center to prepare for the examination, invigilate the examination, review the examination papers and analyze the examination papers before and after the examination. Results: Based on the online examination of 151 eight-year undergraduates in clinical medicine, we found that the time consistency can be achieved through the setting of 'limited time entry' and 'limited time submission' in the system.By adding analysis, induction and comparison questions and reducing memory questions, the overall difficulty coefficient (P=0.81) of the test paper was equivalent to that of the same period of offline test in previous years.Through the rehearsal test setup, teachers and examinees could be familiar with the test process and improve the test equipment.The proportion of students using PC computer platform webpage to answer questions in formal examination was about 2%, higher than that in practice test, and another 4% students were no longer use mobile platform program to answer questions. Conclusion: The overall running of the online examination is stable and the score distribution is reasonable. The choice of examination platform should be applicable to all examinees.Before the examination, we should fully consider the particularity of the online examination scene, and carry out the simulation test and examination plan design in advance.The test paper formation and question setting of the online examination should be adjusted appropriately. © 2021, Editorial Department of Fudan University Journal of Medical Sciences. All right reserved.
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OBJECTIVE: To explore the expression and significance of SAA, CRP and FERR in patients diagnosed with COVID-19. PATIENTS AND METHODS: A total of 225 patients diagnosed with COVID-19 who were admitted to the North Hospital of First Hospital in Changsha, China, from 9th February 2020 to 7th March 2020 were enrolled. Their general data, laboratory test results and levels of SAA, CRP and FERR were extracted from electronic medical records. RESULTS: Age was an important risk factor for the severity of COVID-19 in the patients. Compared with the non-severe group, the severe group showed statistical significance in the levels of total protein, albumin, ALT and AST in liver function, UA in renal function, myocardial enzyme CK-MB and LDH, and immunoglobulin IgG and IgM. The levels of SAA, CRP, and FERR were significantly increased in patients with severe COVID-19. ROC curve analysis results showed that the AUC, from small to large, was as follows: SAA+CRP+FERR, CRP + FERR, SAA + CRP, SAA + FERR, SAA, FERR, and CRP, which indicated the benefit of the combination of the three indicators. The sensitivity and specificity of the combined detection of the three indicators were higher than those of the detection of any single indicator or two combined indicators. A Spearman correlation analysis of the data showed that the initial CRP/SAA, SAA/FERR, and CRP/FERR were positively correlated. The continuous results of SAA, CRP and FERR throughout the study period showed that the values of the severe group on a given day were higher than those of the non-severe group; the values of the two groups peaked on the 5th or 7th day and then decreased, and the decreasing trend of the severe group was more evident. CONCLUSIONS: SAA, CRP and FERR are sensitive serological indicators used to evaluate the severity of COVID-19. The combined detection of serum SAA, FERR, and CRP, which are positively related to COVID-19 infection, offers guiding significance for the occurrence of COVID-19 infection and the severity of the disease. Such detection provides effective detection indicators for the progress and prognosis of COVID-19; these indicators will enable effective intervention measures to be implemented in time and the rates of severe illness and mortality to be reduced.
Subject(s)
C-Reactive Protein/analysis , Coronavirus Infections/diagnosis , Ferritins/blood , Pneumonia, Viral/diagnosis , Serum Amyloid A Protein/analysis , Adult , Age Factors , Aged , Betacoronavirus/isolation & purification , Betacoronavirus/pathogenicity , Biomarkers/blood , COVID-19 , China/epidemiology , Coronavirus Infections/blood , Coronavirus Infections/mortality , Coronavirus Infections/virology , Disease Progression , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/blood , Pneumonia, Viral/mortality , Pneumonia, Viral/virology , Prognosis , Retrospective Studies , SARS-CoV-2 , Sensitivity and Specificity , Severity of Illness IndexABSTRACT
The highly contagious novel coronavirus pneumonia (COVID-19) that broke out in December 2019 has brought huge threats and losses to human society, so it has been the concern of every countries government. Presently, there are no specific drugs for COVID-19; however, a variety of potentially effective antiviral drugs, vaccines, cell therapies, traditional Chinese medicine and other methods are in clinical trials. Liver injury is a common complication of patients receiving COVID-19 treatment and its possible high incidence may affect the outcome of the disease. The pathogenesis of COVID-19 combined with liver injury in existing studies is still unclear, and relevant guidelines and expert consensuses are insufficient for clinical diagnosis and treatment. Therefore, the relevant progress and issues are now reviewed here.