Design and Implementation of Intelligent Truck Based on Azure Kinect

In recent years, due to the impact of COVID-19, the market prospect of non-contact handling has improved and the development potential is huge. This paper designs an intelligent truck based on Azure Kinect, which can save manpower and improve efficiency, and greatly reduce the infection risk of medical staff and community workers. The target object is visually recognized by Azure Kinect to obtain the center of mass of the target, and the GPS and Kalman filter are used to achieve accurate positioning. The 4-DOF robot arm is selected to grasp and transport the target object, so as to complete the non-contact handling work. In this paper, different shapes of objects are tested. The experiment shows that the system can accurately complete the positioning function, and the accuracy rate is 95.56%. The target object recognition is combined with the depth information to determine the distance, and the spatial coordinates of the object centroid are obtained in real time. The accuracy rate can reach 94.48%, and the target objects of different shapes can be recognized. When the target object is grasped by the robot arm, it can be grasped accurately according to the depth information, and the grasping rate reaches 92.67%. © 2023, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.

Sleep quality of first-line medical workers fighting against COVID-19 in Wuhan

[Background] Sleep is closely related to immune function and human health, and adequate sleep is an important foundation for human health. [Objective] This study investigates the sleep status of the first-line medical staff in Wuhan in a fight against the coronavirus disease 2019 (COVID-19) outbreak, provides reference for improving the sleep quality of the first-line medical staff in public health emergencies. [Methods] Through convenience sampling, 112 medical workers (first-line group) who aided the COVID-19 fight in Wuhan and 134 medical staff (non-first-line group) who did not participate in the fight were selected. The Pittsburgh Sleep Quality Index (PSQI) was employed to collect data on the incidence of sleep disorders, time to fall asleep, duration of sleep, sleep efficiency, sleep disorders, use of sleep aid, and daytime functions. In addition, a self-made questionnaire was used to investigate the common concerns and time allocation characteristics of the first-line medical workers in the context of major infectious disease outbreaks. [Results] There were no significant differences between the two groups in demographic variables such as gender, age, job title, educational background, marriage status, number of children, and working years (P > 0.05). In the first-line group, 62 medical workers (55.36%) reported sleep disorders, while in the non-first-line group, 54 medical workers (40.30%) did;the difference was statistically significant (P=0.008). Among the seven components of the PSQI, the median sleep time (component 3) score of the first-line group was 1.5, which was higher than that of the non-first-line group (median 1.0) (P < 0.001);the median sleep efficiency (component 4) score of the first-line group was 1.0, which was higher than that of the non-first-line group (median 0) (P < 0.001). The actual sleep duration of the first-line group [(5.65+/-1.15) h] was lower than that of the non-first-line group [(7.00+/-1.40) h] (P < 0.001). The distributions of common concerns were different between the two group. The top three concerns were being infected (76.79%), exhausted (37.50%), and overloaded (27.68%) in the first-line group, and family members being infected (53.73%), being infected (45.52%), and child care (33.58%) in the non-first-line group. [Conclusion] The first-line medical team members report poor sleep quality, short sleep time, low sleep efficiency, sleep disorders, and many psychological concerns. It is necessary to take appropriate measures to improve their sleep quality.Copyright © 2021, Shanghai Municipal Center for Disease Control and Prevention. All rights reserved.

Frontiers: Unmasking Social Compliance Behavior During the Pandemic

In 2020, as the novel coronavirus spread globally, face masks were recommended in public settings to protect against and slow down viral transmission. People complied to varying extents, and their reactions may have been driven by a variety of psychological fac-tors. Based on the literature on social influence and on mask-wearing, we define three cus-tomer segments: Fully-Compliant customers wear masks, and they seem motivated primarily by concerns about their own health risk. Partially-Compliant customers also wear masks, but with improper and ineffective coverage;our empirical analysis suggests that they are moti-vated primarily by a desire to comply with social norms. Finally, Unmasked customers do not wear masks. We examine changes in shopping behaviors with the onset of the pandemic to corroborate the conjectured mask-wearing motives. We find that the three groups made significantly different behavior changes: Fully-Compliant customers shopped significantly faster and practiced stricter social distancing with the onset of the pandemic, whereas the other two groups did not adjust their shopping duration or social distancing.

Early antiviral therapy of abidol combined with lopinavir/ritonavir and recombinant interferon alpha-2b for patients with COVID-19 in Zhejiang: A multicenter prospective study.

Objective: To compare the efficacy of the combination of abidol, lopinavir/ritonavir plus recombinant interferon alpha-2b (rIFNalpha-2b) and the combination of lopinavir/ritonavir plus rIFNalpha-2b for patients with COVID-19 in Zhejiang province. Method(s): A multicenter prospective study was carried out to compare the efficacy of triple combination antiviral therapy and dual combination antiviral therapy in 15 medical institutions of Zhejiang province during January 22 to February 16, 2020. All patients were treated with rIFNalpha-2b (5 million U, 2 times/d) aerosol inhalation, in addition 196 patients were treated with abidol (200 mg, 3 times/d) + lopinavir/ritonavir (2 tablets, 1 time/12 h) (triple combination group) and 41 patients were treated with lopinavir/ritonavir (2 tablets, 1 time/12 h) (dual combination group). The patients who received triple combination antiviral therapy were further divided into three subgroups: <48 h, 3-5 d and >5 d according the time from the symptom onset to medication starting. The therapeutic efficacy was compared between triple combination group and dual combination group, and compared among 3 subgroups of patients receiving triple combination antiviral therapy. SPSS 17.0 software was used to analyze the data. Result(s): The virus nucleic acid-negative conversion time in respiratory tract specimens was (12.2+/-4.7) d in the triple combination group, which was shorter than that in the dual combination group [(15.0+/-5.0) d] (t=6.159, P<0.01). The length of hospital stay in the triple combination group [12.0 (9.0, 17.0) d] was also shorter than that in the dual combination group [15.0 (10.0, 18.0) d] (H=2.073, P<0.05). Compared with the antiviral treatment which was started within after the symptom onset of in the triple combination group, the time from the symptom onset to the viral negative conversion was 13.0 (10.0, 17.0), 17.0 (13.0, 22.0) and 21.0 (18.0, 24.0) d in subgroups of 48 h, 3-5 d and >5 d, respectively (Z=32.983, P<0.01), while the time from antiviral therapy to viral negative conversion was (11.8+/-3.9), (13.5+/-5.1) and (11.2+/-4.3) d, respectively(Z=6.722, P<0.05). Conclusion(s): The triple combination antiviral therapy of abidol, lopinavir/litonavir and rIFNalpha-2b shows shorter viral shedding time and shorter hospitalization time, compared with the dual combination antiviral therapy;and the earlier starting triple combination antiviral therapy will result in better antiviral efficacy.Copyright © 2020 by the Chinese Medical Association.

Liver injury caused by antiviral agents for COVID-19.

Antiviral therapy is important for COVID-19. Currently, the anti-2019-nCoV drugs in clinical trials include broad-spectrum antiviral drugs (alpha interferon and ribavirin), hemagglutinin inhibitors (arbidol), human immunodeficiency virus protease inhibitors (lopinavir/ritonavir and darunavir/cobicistat), nucleoside analogues (favipiravir and remdesivir) and antimalarial drug (chloroquine);while liver damage may occur in some patients with the medication. This article reviews the research on liver damage associated with anti-2019-nCoV drugs, aiming at promoting the safe and effective antiviral therapy for COVID-19 patients.Copyright © 2020 by the Chinese Medical Association.

Liver injury caused by antiviral agents for COVID-19.

Antiviral therapy is important for COVID-19. Currently, the anti-2019-nCoV drugs in clinical trials include broad-spectrum antiviral drugs (alpha interferon and ribavirin), hemagglutinin inhibitors (arbidol), human immunodeficiency virus protease inhibitors (lopinavir/ritonavir and darunavir/cobicistat), nucleoside analogues (favipiravir and remdesivir) and antimalarial drug (chloroquine);while liver damage may occur in some patients with the medication. This article reviews the research on liver damage associated with anti-2019-nCoV drugs, aiming at promoting the safe and effective antiviral therapy for COVID-19 patients.Copyright © 2020 by the Chinese Medical Association.

Early antiviral therapy of abidol combined with lopinavir/ritonavir and recombinant interferon alpha-2b for patients with COVID-19 in Zhejiang: A multicenter prospective study.

Objective: To compare the efficacy of the combination of abidol, lopinavir/ritonavir plus recombinant interferon alpha-2b (rIFNalpha-2b) and the combination of lopinavir/ritonavir plus rIFNalpha-2b for patients with COVID-19 in Zhejiang province. Method(s): A multicenter prospective study was carried out to compare the efficacy of triple combination antiviral therapy and dual combination antiviral therapy in 15 medical institutions of Zhejiang province during January 22 to February 16, 2020. All patients were treated with rIFNalpha-2b (5 million U, 2 times/d) aerosol inhalation, in addition 196 patients were treated with abidol (200 mg, 3 times/d) + lopinavir/ritonavir (2 tablets, 1 time/12 h) (triple combination group) and 41 patients were treated with lopinavir/ritonavir (2 tablets, 1 time/12 h) (dual combination group). The patients who received triple combination antiviral therapy were further divided into three subgroups: <48 h, 3-5 d and >5 d according the time from the symptom onset to medication starting. The therapeutic efficacy was compared between triple combination group and dual combination group, and compared among 3 subgroups of patients receiving triple combination antiviral therapy. SPSS 17.0 software was used to analyze the data. Result(s): The virus nucleic acid-negative conversion time in respiratory tract specimens was (12.2+/-4.7) d in the triple combination group, which was shorter than that in the dual combination group [(15.0+/-5.0) d] (t=6.159, P<0.01). The length of hospital stay in the triple combination group [12.0 (9.0, 17.0) d] was also shorter than that in the dual combination group [15.0 (10.0, 18.0) d] (H=2.073, P<0.05). Compared with the antiviral treatment which was started within after the symptom onset of in the triple combination group, the time from the symptom onset to the viral negative conversion was 13.0 (10.0, 17.0), 17.0 (13.0, 22.0) and 21.0 (18.0, 24.0) d in subgroups of 48 h, 3-5 d and >5 d, respectively (Z=32.983, P<0.01), while the time from antiviral therapy to viral negative conversion was (11.8+/-3.9), (13.5+/-5.1) and (11.2+/-4.3) d, respectively(Z=6.722, P<0.05). Conclusion(s): The triple combination antiviral therapy of abidol, lopinavir/litonavir and rIFNalpha-2b shows shorter viral shedding time and shorter hospitalization time, compared with the dual combination antiviral therapy;and the earlier starting triple combination antiviral therapy will result in better antiviral efficacy.Copyright © 2020 by the Chinese Medical Association.

Application of glucocorticoids in treatment of COVID-19.

The infection of 2019-nCoV can lead to overexpression of inflammatory factors, triggering cytokine storm and causing serious damage to the body. Glucocorticoids have anti-inflammatory properties and may be an effective treatment option. The use and dosage of glucocorticoids in coronavirus disease 2019 (COVID-19) remains controversial. This article reviews the theoretical basis, clinical evidence, debates and specific measures of glucocorticoids in the treatment of COVID-19, to provide reference for rational application of glucocorticoids in the future.Copyright © 2021 Chinese Medical Association

Application of glucocorticoids in treatment of COVID-19.

The infection of 2019-nCoV can lead to overexpression of inflammatory factors, triggering cytokine storm and causing serious damage to the body. Glucocorticoids have anti-inflammatory properties and may be an effective treatment option. The use and dosage of glucocorticoids in coronavirus disease 2019 (COVID-19) remains controversial. This article reviews the theoretical basis, clinical evidence, debates and specific measures of glucocorticoids in the treatment of COVID-19, to provide reference for rational application of glucocorticoids in the future.Copyright © 2021 Chinese Medical Association

Effect of low-to-moderate dose glucocorticoids on viral clearance in COVID-19: a retrospective study.

Objective: To study the effect of low-to-moderate dose glucocorticoid therapy on viral clearance 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, Zhejiang University School of Medicine were recruited. All patients received oral arbidol and combination of lopinavir/ritonavir or darunavir/cobistitat for antiviral therapy, 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 did not use glucocorticoid (control group). The time of virologic negative conversion in sputum and the time of radiologic recovery in lung since onset were compared between the two groups. 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 (45, 62) and 46 (32, 56) years (chi2=4.365, P<0.05). The clinical conditions at hospital admission were different between the two groups (P<0.01). The severe cases accounted for 52.0%, while moderate cases in the control group accounted for 71.4%. The median times from the onset to virologic negative conversion in the two groups were 15 (13, 20) and 14 (12, 20) days (P>0.05). The median times from onset to radiologic recovery were 13 (11, 15) and 13 (12, 17) days in the two groups (P>0.05). In moderate cases, the median times from the onset to virologic conversion in sputum were 13 (11, 18) days in the glucocorticoid group and 13 (12, 15) days in the control group (P>0.05). The median times from onset to radiologic recovery in lung were 12 (10, 15) and 13 (12, 17) days, respectively (P>0.05). Conclusion(s): Low-to-moderate glucocorticoid treatment has no effect on the time of virus clearance in patients with different clinical types of COVID-19, and also no effect on accelerating radiologic recovery in lung, so it is not recommended.Copyright © 2020 by the Chinese Medical Association.

Effect of low-to-moderate dose glucocorticoids on viral clearance in COVID-19: a retrospective study.

Objective: To study the effect of low-to-moderate dose glucocorticoid therapy on viral clearance 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, Zhejiang University School of Medicine were recruited. All patients received oral arbidol and combination of lopinavir/ritonavir or darunavir/cobistitat for antiviral therapy, 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 did not use glucocorticoid (control group). The time of virologic negative conversion in sputum and the time of radiologic recovery in lung since onset were compared between the two groups. 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 (45, 62) and 46 (32, 56) years (chi2=4.365, P<0.05). The clinical conditions at hospital admission were different between the two groups (P<0.01). The severe cases accounted for 52.0%, while moderate cases in the control group accounted for 71.4%. The median times from the onset to virologic negative conversion in the two groups were 15 (13, 20) and 14 (12, 20) days (P>0.05). The median times from onset to radiologic recovery were 13 (11, 15) and 13 (12, 17) days in the two groups (P>0.05). In moderate cases, the median times from the onset to virologic conversion in sputum were 13 (11, 18) days in the glucocorticoid group and 13 (12, 15) days in the control group (P>0.05). The median times from onset to radiologic recovery in lung were 12 (10, 15) and 13 (12, 17) days, respectively (P>0.05). Conclusion(s): Low-to-moderate glucocorticoid treatment has no effect on the time of virus clearance in patients with different clinical types of COVID-19, and also no effect on accelerating radiologic recovery in lung, so it is not recommended.Copyright © 2020 by the Chinese Medical Association.

Effect of low-to-moderate dose glucocorticoids on viral clearance in COVID-19: a retrospective study.

Objective: To study the effect of low-to-moderate dose glucocorticoid therapy on viral clearance 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, Zhejiang University School of Medicine were recruited. All patients received oral arbidol and combination of lopinavir/ritonavir or darunavir/cobistitat for antiviral therapy, 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 did not use glucocorticoid (control group). The time of virologic negative conversion in sputum and the time of radiologic recovery in lung since onset were compared between the two groups. 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 (45, 62) and 46 (32, 56) years (chi2=4.365, P<0.05). The clinical conditions at hospital admission were different between the two groups (P<0.01). The severe cases accounted for 52.0%, while moderate cases in the control group accounted for 71.4%. The median times from the onset to virologic negative conversion in the two groups were 15 (13, 20) and 14 (12, 20) days (P>0.05). The median times from onset to radiologic recovery were 13 (11, 15) and 13 (12, 17) days in the two groups (P>0.05). In moderate cases, the median times from the onset to virologic conversion in sputum were 13 (11, 18) days in the glucocorticoid group and 13 (12, 15) days in the control group (P>0.05). The median times from onset to radiologic recovery in lung were 12 (10, 15) and 13 (12, 17) days, respectively (P>0.05). Conclusion(s): Low-to-moderate glucocorticoid treatment has no effect on the time of virus clearance in patients with different clinical types of COVID-19, and also no effect on accelerating radiologic recovery in lung, so it is not recommended.Copyright © 2020 by the Chinese Medical Association.

Vaccination with Span, an antigen guided by SARS-CoV-2 S protein evolution, protects against challenge with viral variants in mice

SARS-CoV-2 continues to accumulate mutations to evade immunity, leading to breakthrough infections after vaccination. How researchers can anticipate the evolutionary trajectory of the virus in advance in the design of next-generation vaccines requires investigation. Here, we performed a comprehensive study of 11,650,487 SARS-CoV-2 sequences, which revealed that the SARS-CoV-2 spike (S) protein evolved not randomly but into directional paths of either high infectivity plus low immune resistance or low infectivity plus high immune resistance. The viral infectivity and immune resistance of variants are generally incompatible, except for limited variants such as Beta and Kappa. The Omicron variant has the highest immune resistance but showed high infectivity in only one of the tested cell lines. To provide cross-clade immunity against variants that undergo diverse evolutionary pathways, we designed a new pan-vaccine antigen (Span). Span was designed by analyzing the homology of 2675 SARS-CoV-2 S protein sequences from the NCBI database before the Delta variant emerged. The refined Span protein harbors high-frequency residues at given positions that reflect cross-clade generality in sequence evolution. Compared with a prototype wild-type (Swt) vaccine, which, when administered to mice, induced serum with decreased neutralization activity against emerging variants, Span vaccination of mice elicited broad immunity to a wide range of variants, including those that emerged after our design. Moreover, vaccinating mice with a heterologous Span booster conferred complete protection against lethal infection with the Omicron variant. Our results highlight the importance and feasibility of a universal vaccine to fight against SARS-CoV-2 antigenic drift.

Pathogens inactivation in nutrient recovery from urine: A review

Urine source separation, a kind of new sewage management concept, has made great progress in technology development and application in the past 30 years. However, understanding of the potential microbial risks in reuse of urine derived fertilizer products (UDFPs) in agriculture is still lacking. Outbreak of pandemic of Coronavirus Disease 2019 and more deadly disease caused by Monkeypox strongly sounds the alarm bell to the attention on pathogens in urine and their fate in UDFPs. Therefore, this study presented a comprehensive review on pathogens inactivation in nutrient recovery technologies. The review suggests that technologies using alkaline or heating treatment can effectively reduce pathogens in UDFPs. However, technologies with characteristics such as membrane rejection of nutrients or nutrient adsorption may even concentrate pathogens in their fertilizer products. Based on an overall assessment, connections of technologies and the pathogens inactivation in their UDFPs have been established. This would help to provide a perspective on development of urine treatment technology and management of microbial risks in reusing urine nutrients in agriculture.

Elementary and secondary school students' perceptions toward the use of e-learning under the COVID-19 pandemic: a mixed-methods study

PurposeThe lockdown of schools to control the spread of Coronavirus Disease 2019 (COVID-19) has adversely affected elementary and secondary school students in China. However, little evidence is available that documents their perceptions toward the use of e-learning under the pandemic context. This study aims to explore (1) the underlying determinants influencing the students' intentions to continue e-learning and (2) the role that the COVID-19 pandemic plays in this decision. This study extends the expectation-confirmation model (ECM) through a mixed-methods study.Design/methodology/approachThis study uses a mixed-methods approach. Phase 1 draws conclusions and extracts significant elements related to e-learning during the pandemic by analyzing students' user reviews from platforms. Based on the findings, the authors identify the relevant variables and develop an extended ECM by integrating attitudes and the perceived threat of COVID-19. In Phase 2, the research model is empirically validated using data collected from 36,920 elementary and secondary school students in China. This study uses a mixed-methods approach. Phase 1 draws conclusions and extracts significant elements related to e-learning during the pandemic by analyzing students' user reviews from platforms. Based on the findings, the authors identify the relevant variables and develop an extended ECM by integrating attitudes and the perceived threat of COVID-19. In Phase 2, the research model is empirically validated using data collected from 36,920 elementary and secondary school students in China.FindingsIn Phase 1, the results reveal that students' most concern elements in the COVID-19 pandemic are user perceptions toward e-learning and threat perceptions of COVID-19. In Phase 2, the results reveal that perceived usefulness and attitude are the most significant factors in students' intention to continue. The perceived threat of COVID-19 indirectly influences their intention to continue.Originality/valueThe study extends the ECM with a mixed-methods study to understand students' perceptions toward e-learning during the COVID-19 pandemic. This study can be helpful in related studies in the context of COVID-19-related diseases or other novel scenarios.

[The influence of meteorological factors on SARS-CoV-2 transmission: evidence from laboratory and epidemiological studies].

SARS-CoV-2 has infected more than 600 million people worldwide and caused more than 6 million deaths. The emerging novel variants have made the epidemic rebound in many places. Meteorological factors can affect the epidemic spread by changing virus activity, transmission dynamic parameters and host susceptibility. This paper systematically analyzed the currently available laboratory and epidemiological studies on the association between the meteorological factors and COVID-19 incidence, in order to provide scientific evidence for future epidemic control and prevention, as well as developing early warning system.

A Large-Scale Analysis of COVID-19 Twitter Dataset in a New Phase of the Pandemic

Social media have been awash with news and discussions of the COVID-19 pandemic. It is phenomenal to observe that social media has been the focal venue for people to express their reactions, opinions, and interpretations of the pandemic, given the presence of mixed sources of real information and misinformation. Thus, it is essential to conduct professional assessments of the public views and their evolving nature. Our study aims to extract and assess insights into the reflections of sentiments and topics of the public on Twitter and their dynamics along the timeline of the Delta variant. It highlights the extraordinary influence Twitter, or similar major social media, would have on people to comprehend and decide how to cope with the pandemic. We present findings of extracted sentiments and topics from a large-scale dataset of COVID-related tweets collected for the recent phase of the Delta variant of the pandemic (July-September 2021). We utilized a variety of machine learning algorithms for topic modeling and testing the accuracy of sentiment analysis. Our study shows the dramatic dominance of a positive and objective sentiment rather than a negative and subjective sentiment as well as the shift of prevalent topics during the period of study. The findings indicate the importance of conveying real, rational, and accurate information instead of misinformation on social media to foster the public's awareness and preparedness for a major public emergency incident such as the pandemic. © 2022 IEEE.

DEVELOPMENT AND IMPLEMENTATION OF A MULTICOMPONENT INTERVENTION TO IMPROVE GUIDELINECONCORDANT MANAGEMENT OF PULMONARY NODULES

BACKGROUND: Adherence to guideline-concordant management of incidentally detected pulmonary nodules (PNs) is frequently poor. We designed and implemented a division-level intervention to improve Fleischner society guideline adherence at our institution. METHODS: Our intervention included: (1) radiology report templates for documentation of PNs, (2) generation of daily reports of incidentally identified PNs, (3) a population health coordinator who documented PN identification in the electronic health record (EHR) and managed patient outreach, and (4) EHR templates for clinician documentation of disclosure to patients and clinical care plan. Outcomes were rates of PN disclosure and completion of recommended surveillance chest computed tomography (CT) or sub specialist evaluation. Outcomes were assessed in patients with a PN identified before (01/02/ 2018-03/31/2019) and after (04/01/2019-09/30/2020) implementation of the intervention in 4 primary care practices. RESULTS: Pre-and post-implementation cohorts included 395 and 432 patients, respectively. Mean age was 65.1±10.8 vs 65.0±11.8 (p=0.881) and 59.5% vs 60.2% were female (p=0.895). Race was White in 52.4% vs 43.3%, Black in 39.5% vs 45.1%, and other 8.1%vs 11.6%(p=0.166). Recommended management was surveillance chest CT (72.4% vs 73.6%), subspecialist referral (21.0% vs 13.7%), or no further imaging (6.6% vs 12.7%;p=0.001). Disclosure of PNs increased from 78.5% to 94.9%, an improvement of 16.4% (95% CI 11.9-21.0%). Surveillance CT ordering increased from 66.4% [n=190/286] to 88.7% [n=282/318], an improvement of 22.3% (95% CI 15.8-28.7%) and CT completion increased from 67.1% [n=192/286] to 85.5% [n=272/318], an improvement of 18.4% (95% CI 11.7-25.1%). When CT was completed >30 days after the recommended time interval, median delay was reduced by 66.5 days (163.5 [n=72] vs 97.0 [n=97], p=0.004), despite post-intervention overlapping with the COVID-19 pandemic (Figure 1). The rate of completed sub specialist evaluation was similar (94.0% [n=78/83] vs 93.9% [n=46/49], p=1). CONCLUSIONS: A multicomponent division-level intervention improved rates of PN disclosure and surveillance CT ordering and completion. Our findings support expansion of system-level approaches that standardize and automate processes to improve guideline adherence.

Preparation and preliminary application of antiserum against S protein of SARS-CoV-2

Objective To prepare antiserum against S protein of SARS-CoV-2 and preliminarily develop a method for determination of antigen content in inactivated SARS-CoV-2 vaccine. Methods Goats and rabbits were immunized with recombinant S protein of SARS-CoV-2, and the obtained antisera were determined for titer by indirect ELISA and neutralization assay and for specificity by Western blot, then purified by protein G resin affinity chro-matography. A sandwich ELISA for determination of antigen content of inactivated SARS-CoV-2 vaccine was developed by using purified goat antibody as capture antibody and purified rabbit antibody as detection antibody. Results The titer of antiserum of goats after immunization for 4 times reached 220 000 by ELISA and 1 536 by neutralization assay, while that of rabbits after immunization for 3 times reached 220 000 by ELISA and 4 096 by neutralization assay. Both goat and rabbit antibodies showed specific binding to the S protein of SARS-CoV-2. A double antibody sandwich ELISA method for determination of antigen content was successfully developed by using the purified antibodies, which showed a good linearity with a R2 value of more than 0. 99. Conclusion High titer goat and rabbit antisera against S protein of SARS-CoV-2 were prepared successfully, and double antibody sandwich ELISA method for determination of antigen content of inactivated SARS-CoV-2 vaccine was preliminarily developed. © 2021 Changchun Institute of Biological Products. All rights reserved.