Degradation and dechlorination of trichloroacetic acid induced by an in situ 222 nm KrCl* excimer radiation.

Since the coronavirus disease 2019 (COVID-19) pandemic epidemic, the excessive usage of chlorinated disinfectants raised the substantial risks of disinfection by-products (DBPs) exposure. While several technologies may remove the typical carcinogenic DBPs, trichloroacetic acid (TCAA), their application for continuous treatment is limited due to their complexity and expensive or hazardous inputs. In this study, degradation and dechlorination of TCAA induced by an in situ 222 nm KrCl* excimer radiation as well as role of oxygen in the reaction pathway were investigated. Quantum chemical calculation methods were used to help predict the reaction mechanism. Experimental results showed that UV irradiance increased with increasing input power and decreased when the input power exceeded 60 W. Decomposition and dechlorination were simultaneously achieved, where around 78% of TCAA (0.62 mM) can be eliminated and 78% dechlorination within 200 min. Dissolved oxygen showed little effect on the TCAA degradation but greatly boosted the dechlorination as it can additionally generate hydroxyl radical (•OH) in the reaction process. Computational results showed that under 222 nm irradiation, TCAA was excited from S0 to S1 state and then decayed by internal crossing process to T1 state, and a reaction without potential energy barrier followed, resulting in the breaking of C-Cl bond and finally returning to S0 state. Subsequent C-Cl bond cleavage occurred by a barrierless •OH insertion and HCl elimination (27.9 kcal/mol). Finally, the •OH attacked (14.6 kcal/mol) the intermediate byproducts, leading to complete dechlorination and decomposition. The KrCl* excimer radiation has obvious advantages in terms of energy efficiency compared to other competitive methods. These results provide insight into the mechanisms of TCAA dechlorination and decomposition under KrCl* excimer radiation, as well as important information for guiding research toward direct and indirect photolysis of halogenated DBPs.

Impact of the COVID-19 pandemic on air pollution from jet engines at airports in central eastern China.

Aircraft engine emissions (AEEs) generated during landing and takeoff (LTO) cycles are important air pollutant sources that directly impact the air quality at airports. Although the COVID-19 pandemic triggered an unprecedented collapse in the civil aviation industry, it also relieved some environmental pressure on airports. To quantify the impact of COVID-19 on AEEs, the amounts of three typical air pollutants (i.e., HC, CO, and NOx) from LTO cycles at airports in central eastern China were estimated before and after the pandemic. The study also explored the temporal variation and the spatial autocorrelation of both the emission quantity and the emission intensity, as well as their spatial associations with other socioeconomic factors. The results illustrated that the spatiotemporal distribution pattern of AEEs was significantly influenced by the policies implemented and the severity of COVID-19. The variations of AEEs at airports with similar characteristics and functional positions generally followed similar patterns. The results also showed that the studied air pollutants present positive spatial autocorrelation, and a positive spatial dependence was found between the AEEs and other external socioeconomic factors. Based on the findings, some possible policy directions for building a more sustainable and environment-friendly airport group in the post-pandemic era were proposed. This study provides practical guidance on continuous monitoring of the AEEs from LTO cycles and studying the impact of COVID-19 on the airport environment for other regions or countries.

A rare case of drug-induced bradycardia associated with the just low dose use of methylprednisolone in a child with COVID-19.

Methylprednisolone (MP) is usually used to reduce inflammation reaction and tissue damage, which may have a beneficial treatment effect on coronavirus disease 2019 (COVID-19). However, we present the case of a child who manifests significant bradycardia with the use of just low dose MP on the premise of the long-term use of arbidol. Arbidol can affect the activity of CYP3A4, which is also a key metabolic enzyme of MP by competitive inhibition, and which is easy to aggravate the side effects of MP. Therefore, more attention should be paid to bradycardia occurrence in the patient with COVID-19 when MP is considered in COVID-19.

Spatial-Temporal Patterns of Air Pollutant Emissions From Landing and Take-Off Cycles in the Yangtze River Delta of China During the COVID-19 Outbreak.

The global aviation industry has been experiencing catastrophic disruption since the beginning of 2020 due to the unprecedented impact of the COVID-19 pandemic on air traffic. Although the decline in regular commercial air travel has caused tremendous economic loss to aviation stakeholders, it has also led to the reduction in the amount of recorded air pollutants. Most of the aircraft emissions are released during the cruise phase of flight, however they have relatively small impact on humans due to the fact that those emissions are released directly into the upper troposphere and lower stratosphere. Therefore, the scope of this study is to investigate the ground-level aircraft emissions from landing and take-off (LTO) cycles, as they have a greater influence on the ambient environment of the airports in a specific region. In this paper, we study the variation of typical air pollutant concentrations (i.e., HC, CO, and NOx) from the LTO cycles during the outbreak of COVID-19 pandemic in both temporal and spatial scales. These ground-level emissions are estimated for the 22 airports in the Yangtze River Delta, China. The results indicate that the variation pattern of the three air pollutants were significantly influenced by the dramatic onset of the COVID-19 pandemic, as well as the pertinent policies to suppress the spread of the virus. The results also reveal non-uniform distribution of the emission quantified at different airports. It is noticeable that the emission quantity generally declined from the east coast to the central and western part of the research region. Furthermore, discrepancies in the target markets also create disparities in the variation pattern of the emissions at different airports under the context of COVID-19.

Elevated cardiac biomarkers may be effective prognostic predictors for patients with COVID-19: A multicenter, observational study.

PURPOSE: The coronavirus disease 19 (COVID-19) has become a global health event. Cardiac biomarkers like creatine kinase isoenzyme (CK-MB), myoglobin, and high-sensitivity troponin T were usually elevated in early stages. This study aimed to investigate whether the elevated cardiac biomarkers could become effective prognostic predictors for COVID-19 patients. METHODS: The present study involved 357 COVID-19 patients. The potential predictors for two study outcomes (in-hospital death and recovery status) in 28 days were selected by LASSO regression analysis. Prognostic values of cardiac biomarkers selected were evaluated using the receiver operating characteristic curve (ROC) and the area under ROC (AUC). RESULTS: After 28-day follow-up, overall 357 patients were divided into death group (n = 25) and survival group (n = 332), or non-recovery group (n = 43) and recovery group (n = 314). The LASSO regression analysis showed elevated CK-MB and myoglobin were independent risk predictors for in-hospital death, and CK-MB and myoglobin were also independent risk predictors for non-recovery. The AUC of CK-MB and myoglobin for in-hospital death were 0.862 (95%CL: 0.804-0.920, p < 0.001) and 0.838 respectively (95%CL: 0.729-0.947, p < 0.001). The AUC of CK-MB and myoglobin for non-recovery were 0.839 (95%CL: 0.786-0.892, p < 0.001) and 0.841 (95%CL: 0.765-0.918, p < 0.001) respectively. We also found AUC of combined use of CK-MB and myoglobin for in-hospital death and non-recovery were 0.883 (95CL: 0.813-0.952, p < 0.001), and 0.873 (95%CL: 0.817-0.930, p < 0.001) respectively. CONCLUSIONS: In patients with COVID-19, elevated CK-MB and myoglobin on admission may be effective predictors for adverse outcomes, and combined use of CK-MB and myoglobin had a better performance for prediction.

Smart homes that detect sneeze, cough, and face touching.

Coughing, sneezing, and face touching activities are three primary ways of spreading disease. With the onset of COVID-19 it is paramount to monitor these activities at home and practice good hygiene. To help stop the spread of disease, we have developed a wireless sensing system capable of detecting voluntary coughs, sneezes, and face touching with alert based notifications sent to a mobile application. Our system uses radio frequency technology to capture motion, speed, direction, and range information from human activities. It does this by using a combination of a continuous wave Doppler and frequency modulated continuous wave radar. By observing a set of features related to the sensed motion, we designed a set of fuzzy logic IF-THEN rules that can differentiate each activity from each other with an overall accuracy of 96%. In addition, our system enables smart homes to detect and localize these activities at different distances up to 2.74 m, through walls, and with multiple people. We envision our system helping not only with prevention of COVID-19, but supporting contact tracing efforts by monitoring people's activities at home.

The Prognostic Nutritional Index is associated with mortality of COVID-19 patients in Wuhan, China.

BACKGROUND: Declared as pandemic by WHO, the coronavirus disease 2019 (COVID-19) pneumonia has brought great damage to human health. The uncontrollable spread and poor progression of COVID-19 have attracted much attention from all over the world. We designed this study to develop a prognostic nomogram incorporating Prognostic nutritional index (PNI) in COVID-19 patients. METHODS: Patients confirmed with COVID-19 and treated in Renmin Hospital of Wuhan University from January to February 2020 were included in this study. We used logistic regression analysis to find risk factors of mortality in these patients. A prognostic nomogram was constructed and receiver operating characteristics (ROC) curve was drawn to evaluate the predictive value of PNI and this prognostic model. RESULTS: Comparison of baseline characteristics showed non-survivors had higher age (P < .001), male ratio (P = .038), neutrophil-to-lymphocyte ratio (NLR) (P < .001), platelet-to-lymphocyte ratio (PLR) (P < .001), and PNI (P < .001) than survivors. In the multivariate logistic regression analysis, independent risk factors of mortality in COVID-19 patients included white blood cell (WBC) (OR 1.285, P = .039), PNI (OR 0.790, P = .029), LDH (OR 1.011, P < .015). These three factors were combined to build the prognostic model. Area under the ROC curve (AUC) of only PNI and the prognostic model was 0.849 (95%Cl 0.811-0.888) and 0.950 (95%Cl 0.922-0.978), respectively. And calibration plot showed good stability of the prognostic model. CONCLUSION: This research indicates PNI is independently associated with the mortality of COVID-19 patients. Prognostic model incorporating PNI is beneficial for clinicians to evaluate progression and strengthen monitoring for COVID-19 patients.

Dynamic changes in peripheral blood lymphocyte subsets in adult patients with COVID-19.

INTRODUCTION: Coronavirus disease 2019 (COVID-19), caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread widely. The aim of this study was to investigate the dynamic changes in peripheral blood lymphocyte subsets in adult patients with COVID-19. METHODS: The electronic medical records were reviewed. Data including demographic characteristics, clinical manifestations, comorbidities, laboratory data, and radiological examinations of 435 hospitalized COVID-19 patients with a confirmed SARS-CoV-2 viral infection were extracted and analyzed retrospectively. Lymphocyte subset counts at each week after the onset of the illness were compared with those of the other weeks of illness and with those of control individuals. RESULTS: The various lymphocyte subsets (CD3+, CD4+, CD8+, CD19+, and CD16/56+) were below the normal ranges at 1 week after the onset of illness, reaching a nadir during the second week. They increased gradually during the third week and returned to normal levels in the fifth week, but were still lower than those of the healthy controls. The CD3+, CD4+, and CD8+ counts were significantly lower in patients with severe disease compared to those with non-severe disease, and in patients who died compared to those who recovered. DISCUSSION: This research indicates that the levels of peripheral blood lymphocyte subsets (CD3+, CD4+, and CD8+) are associated with disease progression and severity, and with the prognosis in patients with COVID-19. Dynamic monitoring of human immune function is one of the indicators for evaluating the severity of disease and the prognosis of COVID-19 patients, and is useful for formulating appropriate treatment strategies.

Analysis of clinical features and related factors of coronavirus disease 2019 in Shanghai

Objective • To explore the common clinical features of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-infected local patients in Shanghai and their related influencing factors. Methods • A total of 320 patients admitted to Shanghai Public Health Clinical Center from January to March 2020 and diagnosed as having coronavirus disease 2019(COVID-19) were selected. Clinical data of the patients were collected to analyze their characteristics. Using the statistical operation formula of R language, the correlation analysis of hospitalization days, days of increased hypersensitive C-reactive protein concentration (allergic days), days of lung CT improvement (CT days), and days required for nucleic acid turning negative with the main clinical manifestations and laboratory data was carried out. The correlation factors affecting the above four variables were analyzed. Results • Among the 320 patients, the proportions of mild type, moderate type, serious type and critical type were 6.25%, 83.44%, 6.88% and 3.44%, respectively;91.25% of them had a history of exposure to Hubei. The proportions of fever, cough, sputum and fatigue were 79.06%, 46.56%, 21.56% and 15.31%, respectively. Spearman correlation analysis showed that the concentrations of lactate dehydrogenase, interleukin-2(IL-2) and IL-6 were positively correlated with the above four variables, respectively (all P<0.05), albumin concentration was negatively correlated with allergic days (P=0.018), and CD4+ cell count was negatively correlated with CT days and days required for nucleic acid turning negative (both P<0.05). Stepwise multiple linear regression analysis showed that procalcitonin (PCT) concentration was negatively correlated with hospitalization days, CT days and allergic days (both P<0.05), and disease type was positively correlated with hospitalization days, allergic days, CT days and days required for nucleic acid turning negative (all P<0.05). Conclusion • Moderate type is common in the local patients in Shanghai;fever, cough and fatigue are common symptoms, and most of the patients are accompanied by lung CT abnormalities. The therapeutic effect and prognosis of these patients are closely related to disease type, concentrations of PCT and IL-6, as well as CD4+ cell count.