Key knowledge domains for maritime shipping executives in the digital era: a knowledge-based view approach

With the emergence of disruptive technologies and digital acceleration caused by COVID-19, educating the maritime workforce by equipping them with relevant knowledge is crucial to the industry’s success. Drawing from the knowledge-based view and business logistic management framework, the objective of this study was to construct a framework that identifies and ranks existing and upcoming relevant knowledge domains and their sub-domains for maritime shipping executives. After reviewing the literature, five domains – digitalisation, maritime business, sustainability, personnel development, and supply chain management (SCM) – and 23 sub-knowledge domains were developed. Surveys were conducted with shipping company managers in Singapore and their responses were analysed using the fuzzy analytic hierarchy process methodology. The results revealed that digitalisation knowledge was the most important, followed by maritime business, personnel development, sustainability, and SCM knowledge. Overall, this research has updated the knowledge and competency framework for maritime shipping executives, contributed to research on the interface between technology and knowledge management, and informed education strategies. [ FROM AUTHOR] Copyright of Technology Analysis & Strategic Management is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Model-Based Evaluation of Transmissibility and Intervention Measures for a COVID-19 Outbreak in Xiamen City, China

Background In September 2021, there was an outbreak of coronavirus disease 2019 (COVID-19) in Xiamen, China. Various non-pharmacological interventions (NPIs) and pharmacological interventions (PIs) have been implemented to prevent and control the spread of the disease. This study aimed to evaluate the effectiveness of various interventions and to identify priorities for the implementation of prevention and control measures. Methods The data of patients with COVID-19 were collected from 8 to 30 September 2021. A Susceptible-Exposed-Infectious-Recovered (SEIR) dynamics model was developed to fit the data and simulate the effectiveness of interventions (medical treatment, isolation, social distancing, masking, and vaccination) under different scenarios. The effective reproductive number (Reff) was used to assess the transmissibility and transmission risk. Results A total of 236 cases of COVID-19 were reported in Xiamen. The epidemic curve was divided into three phases (Reff = 6.8, 1.5, and 0). Notably, the cumulative number of cases was reduced by 99.67% due to the preventive and control measures implemented by the local government. In the effective containment stage, the number of cases could be reduced to 115 by intensifying the implementation of interventions. The total number of cases (TN) could be reduced by 29.66–95.34% when patients voluntarily visit fever clinics. When only two or three of these measures are implemented, the simulated TN may be greater than the actual number. As four measures were taken simultaneously, the TN may be <100, which is 57.63% less than the actual number. The simultaneous implementation of five interventions could rapidly control the transmission and reduce the number of cases to fewer than 25. Conclusion With the joint efforts of the government and the public, the outbreak was controlled quickly and effectively. Authorities could promptly cut the transmission chain and control the spread of the disease when patients with fever voluntarily went to the hospital. The ultimate effect of controlling the outbreak through only one intervention was not obvious. The combined community control and mask wearing, along with other interventions, could lead to rapid control of the outbreak and ultimately lower the total number of cases. More importantly, this would mitigate the impact of the outbreak on society and socioeconomics.

Antibody Persistence and Safety through 6 Months after Heterologous Orally Aerosolised Ad5-nCoV in individuals primed with two-dose CoronaVac previously (preprint)

Background: Heterologous orally administered adenovirus type-5 vector-based COVID-19 vaccine (Ad5-nCoV) in individuals who were primed with two-dose CoronaVac (an inactivated SARS-CoV-2 vaccine, by Sinovac) previously, has been reported to be safe and highly immunogenic within 28 days post-boosting. However, antibody persistence and safety up to 6 months of this regimen are not been reported yet. Methods: This is a randomized, open label, single-center trial on safety and immunogenicity of heterologous boost immunization with an orally administered aerosolised Ad5-nCoV vs. homologous boost immunization with CoronaVac after two-dose priming with CoronaVac in Chinese adults aged 18 years and older (NCT05043259). We followed the participants in this trial, including 140 in the low-dose aerosolised Ad5-nCoV group, 139 in the high-dose aerosolised Ad5-nCoV group, and 140 in the CoronaVac group for 6 months. Neutralising antibodies (NAbs) against live wild-type SARS-CoV-2 virus and omicron variant, and receptor-binding domain (RBD)-specific IgG antibodies were detected in serum samples collected at 28 days, 3 months, and 6 months after the booster dose. Serious adverse events (SAEs) were documented till month 6. Results: The low-dose and high-dose heterologous boost immunisation groups had NAb GMTs against live wild-type SARS-CoV-2 of 1937.3 [95% CI 1466.9, 2558.4] and 1350.8 [95% CI 952.6, 1915.3], which were 26.4 folds and 18.4 folds higher than that the CoronaVac group did (73.5 [95%CI 52.3, 103.3]) at 28 days. The low-dose and high-dose heterologous boost immunisation groups had NAb GMTs against live wild-type SARS-CoV-2 of 530.1 (95% CI 412.5, 681.1) and 457.6 (95%CI 349.4, 599.2), which were 26.0 folds and 22.4 folds higher than that the CoronaVac group did (20.4 [95%CI 14.3, 29.1]) at 3 months, respectively. At 6 months, the low-dose and high-dose heterologous booster groups had NAb GMTs against live wild-type SARS-CoV-2 of 312.9 (95%CI 237.7, 411.8) and 251.1 (95%CI 178.2, 354.0), which were 30.1 folds and 24.1 folds higher than the CoronaVac group did (10.4 [95%CI 7.8, 14.0]), respectively. Additionally, the low-dose and high-dose heterologous booster groups had NAb GMTs against live omicron variant of 52.0 (95%CI 37.2, 72.6) and 23.1 (95%CI 15.7, 33.9) at 28 days, 27.9 (95% CI 18.8, 41.3) and 23.3 (95%CI 16.2, 33.3) at 3 months, 16.0 (95%CI 10.9, 23.5) and 12.0 (95%CI 8.5, 16.8) at 6 months, respectively. However, nearly all participants had no detectable NAbs for omicron variant in the CoronaVac group at either 28 days, 3 months, or 6 months. No vaccine-related SAEs were observed. Conclusions: These data suggested that heterologous aerosolised Ad5-nCoV following two-dose CoronaVac priming was safe and persistently more immunogenic than three-dose CoronaVac, although immune responses waned over time.

Heterologous CoronaVac plus Ad5-nCOV versus homologous CoronaVac vaccination among elderly: a phase 4, non-inferiority, randomized study (preprint)

Importance People over 60 developed less protection after two doses of inactivated COVID-19 vaccine than younger people. Heterologous vaccination might provide greater immunity and protection against variants of concern. Objective To assess the safety and immunogenicity of a heterologous immunization with an adenovirus type 5-vectored vaccine (Convidecia) among elderly who were primed with an inactivated vaccine (CoronaVac) previously. Design An observer-blind, randomized (1:1) trial, conducted from August 26 to November 13, 2021. Setting A single center in Jiangsu Province, China. Participants 299 participants aged 60 years and olderof them 199 primed with two doses of CoronaVac in the past 3-6 months and 100 primed with one dose of CoronaVac in the past 1-2 months. Intervention Convidecia or CoronaVac as boosting dose Main Outcomes and Measures Geometric mean titers (GMTs) of neutralizing antibodies against wild-type SARS-CoV-2, and Delta and Omicron variants 14 days post boosting, and adverse reactions within 28 days. Results In the three-dose regimen cohort (n=199; mean (SD) age, 66.7 (4.2) years; 74 (37.2%) female), 99 and 100 received a third dose of Convidecia (group A) and CoronaVac (group B), respectively. In the two-dose regimen cohort (n=100; mean (SD) age, 70.5 (6.0) years; 49 (49%) female), 50 and 50 received a second dose of Convidecia (group C) and CoronaVac (group D), respectively. GMTs of neutralizing antibodies against wild-type SARS-CoV-2 at day 14 were 286.4 (95% CI: 244.6, 335.2) in group A and 48.2 (95% CI: 39.5, 58.7) in group B, with GMT ratio of 6.2 (95% CI: 4.7, 8.1), and 70.9 (95% CI: 49.5, 101.7) in group C and 9.3 (95% CI: 6.2, 13.9) in group D, with GMT ratio of 7.6 (95% CI: 4.1, 14.1). There was a 6.3-fold (GMTs, 45.9 vs 7.3) and 7.5-fold (32.9 vs 4.4) increase in neutralizing antibodies against Delta and Omicron variants in group A, respectively, compared with group B. However, there was no significant difference between group C and group D. Both heterologous and homologous booster immunizations were safe and well tolerated. Conclusions and Relevance Heterologous prime-boost regimens with CoronaVac and Convidecia induced strong neutralizing antibodies in elderly, which was superior to that induced by the homologous boost, without increasing safety concerns. Trial Registration Clinical Trials.gov NCT04952727

Heterologous prime-boost immunization with CoronaVac and Convidecia (preprint)

ABSTRACT Background The safety and immunogenicity of heterologous prime-boost COVID-19 vaccine regimens with one shot of a recombinant adenovirus type-5-vectored COVID-19 vaccine Convidecia has not been reported. Methods We conducted a randomized, controlled, observer-blinded trial of heterologous prime-boost immunization with CoronaVac and Convidecia in healthy adults 18-59 years of age. Eligible participants who were primed with one or two doses of CoronaVac were randomly assigned at a 1:1 ratio to receive a booster dose of Convidecia or CoronaVac. Participants were masked to the vaccine received but not to the three-dose or two-dose regimen. The occurrences of adverse reactions within 28 days after the vaccination were documented. The geometric mean titers of neutralizing antibodies against live SARS-CoV-2 virus were measured at 14 and 28 days after the booster vaccination. Results Between May 25 and 26, 2021, a total of 300 participants were enrolled. Participants who received a booster shot with a heterologous dose of Convidecia reported increased frequencies of solicited injection-site reactions than did those received a homogeneous dose of CoronaVac, but frequencies of systemic reactions. The adverse reactions were generally mild to moderate. The heterologous immunization with Convidecia induced higher live viral neutralizing antibodies than did the homogeneous immunization with CoronaVac (197.4[167.7, 232.4] vs. 33.6[28.3, 39.8] and 54.4[37. 9, 78.0] vs. 12.8[9.3, 17.5]) at day 14 in the three- and two-dose regimen cohort, respectively. Conclusions The heterologous prime-boost regimen with Convidecia after the priming with CoronaVac was safe and significantly immunogenic than a homogeneous boost with CoronaVac ( ClinicalTrials.gov , number NCT04892459 ).

Changes in the Pathogenic Spectrum of Acute Respiratory Tract Infections During the COVID-19 Epidemic in Beijing, China (preprint)

Background: Public health measures against COVID-19 may influence other disease epidemics. Many countries have reported significant reductions in influenza activity in 2020–2021, but the prevalence of other respiratory pathogens during the COVID-19 pandemic has rarely been reported, especially in China.Methods: Data from the Respiratory Pathogen Surveillance System in Beijing were analyzed to compare pathogen infection rates before the COVID-19 (from 1 February 2015 to 31 January 2020) and during the COVID-19 (from 1 February 2020 to 31 January 2021).Findings: Among 41630 acute respiratory tract infections 13630 had at least one pathogen positive result, which decreased from 32·16% (95% CI 31·69%, 32·64%) before the COVID-19 to 10·97% (95% CI 10·03%, 11·96%) during the COVID-19, representing a 65·90% decrease (P<0·001). The positivity rate fluctuated with the strictness of public health measures. Before the COVID-19 epidemic, the top five of the pathogenic spectrums were IFV (26·27%), MP (19·30%), HPIV (11·80%), HRV (9·38%), and EV (8·38%), while during the COVID-19, the top five were seasonal HCoV (21·10%), HRV (18·99%), HPIV (14·98%), IFV (13·08%), and RSV (10.76%).Interpretation: The prevalence of respiratory pathogens decreased significantly during the COVID-19, closely relating to public health measures against COVID-19; these measures can serve as useful strategies for the prevention and control of other respiratory tract infections.Funding Statement: The National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases in China (2017ZX10103004).Declaration of Interests: FH received funds from the National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases in China (2017ZX10103004). All other authors declare no competing interests.Ethics Approval Statement: Ethics approval for the protocol of this study was obtained from the Ethics Committee of the BJCDC. Written informed consent was obtained.

Poor sleep quality, anxiety and depression are associated with an increased suicide risk in patients with coronavirus disease 2019

Objective: To evaluate suicide risk, sleep quality and psychological status of patients with coronavirus disease 2019 (COVID-19) and analyze the factors contributing to a high suicide risk in these patients.

Parking Under the Sun: Solar Heating As a Strategy for Passively Disinfecting COVID-19 in Passenger Vehicles During Warm-Hot Weather (preprint)

Shared passenger vehicles (taxis, Uber, other drivers-for-hire services) are common in daily transportation. The confined, enclosed space as well as commonly touched surfaces in those sub-environments pose elevated risks of COVID-19 transmission via respiratory, contact, and airborne routes. Current regulatory guidelines rely on voluntary acts from passengers on wearing face coverings while require cleaning and disinfecting by drivers, with gaps left between drivers’ shifts and transmission from non-symptomatic individuals. A labor-intensive procedure, repetitive manual cleaning and disinfecting may present a nuisance for some drivers and can be ineffective in areas that are difficult to access. There is an urgent need to evaluate other strategies to mitigate the risks of COVID-19 infection in passenger vehicles. Since the persistence of the novel coronavirus is sensitive to ambient temperatures, and that inactivation could be achieved within minutes to half an hour at 50–60 °C, solar heating – by parking vehicles under direct sunlight with doors and windows closed – presents a viable strategy for passively disinfecting COVID-19 in vehicle interiors during warm-to-hot weather. To demonstrate this approach, we measured the temperatures in a white compact-size sedan left in a parking lot under direct sunlight. Air temperatures increased rapidly in the cabin during the first 30–40 min, followed by steady increases in the next hour, then plateaued after reaching 52–57 °C at 90 min. Spatial variations (5 ± 1 °C) were found at four diagonal points in the front and back seat at the breathing and knee heights of an average seated adult, with higher temperatures registered in the front and the upper zone. The results supported our hypothesis that hot air generated by solar heating in enclosed objects provides a viable means of thermal inactivation for COVID-19, in a passive manner that does not involve chemical use, laborious work, or waste discharge to surrounding environments.

SARS-CoV-2 Spike protein variant D614G increases infectivity and retains sensitivity to antibodies that target the receptor binding domain (preprint)

The SARS-CoV-2 spike (S) protein variant D614G supplanted the ancestral virus worldwide in a matter of months. Here we show that D614G was more infectious than the ancestral form on human lung cells, colon cells, and cells rendered permissive by ectopic expression of various mammalian ACE2 orthologs. Nonetheless, D614G affinity for ACE2 was reduced due to a faster dissociation rate. Assessment of the S protein trimer by cryo-electron microscopy showed that D614G disrupts a critical interprotomer contact and that this dramatically shifts the S protein trimer conformation toward an ACE2-binding and fusion-competent state. Consistent with the more open conformation, neutralization potency of antibodies targeting the S protein receptor-binding domain was not attenuated. These results indicate that D614G adopts conformations that make virion membrane fusion with the target cell membrane more probable but that D614G retains susceptibility to therapies that disrupt interaction of the SARS-CoV-2 S protein with the ACE2 receptor.

A Randomized Controlled Study of Muscle Training Exercise Based Pulmonary Rehabilitation on Activity of Daily Living in Patients with Coronavirus Disease 2019 (preprint)

Background: Hospitalized patients with Coronavirus Disease 2019 (COVID-19) pneumonia showed a severve loss of muscle mass and strength over admission. Therefore, early physical interventions might be conducive to prevent disability and fasten recovery. Methods: We designed a prospective, randomized controlled trial to identify the effectiveness and safety of pulmonary rehabilitation based on muscle exercise in COVID-19 patients. The study was conducted between February 7th and March 31st 2020 in Union Hospital. Patients were randomly assigned to the pulmonary rehabilitation exercise group or the control group. Primary outcome was improvement of activity of daily living (ADL). Secondary outcome was changes of muscle strength assessed by manual muscle test (MMT) and arterial blood gas analysis. Length of hospital staying (LOS) and adverse events related to physical activity were also observed.Results: A total of sixty patients were in analysis, and thirty patients were in PR group. Patients had a mean age of 54.43±10.57 years. A statistically and clinically significant increase in ADL was observed in PR group (75.00 [66.25,90.00] to 100.00 [100.00,100.00], p<0.001). We also found that the improvement of ADL was related to younger age and higher PaO2 (p<0.01). Both groups had MMT improvement and there was no statistical difference between groups. There was a significant increase in PaO2 (80.23±6.49 vs. 90.47±7.82, respectively, p<0.001) between two groups before discharge. There was no statically significant difference in LOS between study group and control group (p=0.62). None of these patients had severe complications during the study.Conclusions: The protocal of pulmonary rehabilitation based on muscle training exercise was feasible in COVID-19 patients and it might accelerate recovery in ADL as compared with the spontaneous recovery in the control group.Clinical Trial Registration: ChiCTR, ChiCTR2000032457. Registered 29 April 2020- Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=52925.

Mental Health Status of Adolescents after Family Confinement During the COVID-19 Outbreak (preprint)

Background: With the global spread of Coronavirus Disease 2019 (COVID-19), governments around the world have implemented strategies for closing schools and teaching online from home. However, the psychological impact of family confinement on adolescents has not been examined. Methods: From November 2019 to January 2020, just before the COVID-19 outbreak, 14,241 Chinese teenagers aged 12-17 years from 5 middle schools across North China were surveyed in the first round of the national mental health investigation of adolescents. They were assessed with paper questionnaires, including the Chinese version of the 9-item Patient Health Questionnaire, the 7-item Generalized Anxiety Disorder Scale, the short form of the Childhood Trauma Questionnaire, and the Connor-Davidson Resilience Scale. After two months of home confinement, by March 2020, 10,768 of them were re-evaluated online using the same scales. Propensity score matching analysis was performed to analyze the psychological status of adolescents who reported potential risk of exposure to COVID-19. Findings: The first survey round yielded 13,637 valid questionnaires, on which 51.51% reported depressive symptoms and 38.53% reported anxiety symptoms. The second round yielded 10,216 valid questionnaires, on which the rates decreased to 38.29% and 23.73% respectively (all P<0.0001). Of the 10,216 adolescents, 223 reported potential risk of exposure to COVID-19. Propensity score matching analysis showed that adolescents with potential exposure risks had significantly higher rates of depression (60.54% vs 45.95% P=0.002) and anxiety (41.26% vs 28.83% P=0.007) symptoms than risk-free adolescents. Multivariate logistic regression analysis showed that potential exposure risk to COVID-19 was an independent risk factor for depression symptoms (OR, 2.241; 95%CI, 1.659-3.027; PInterpretations: Long-term home confinement had no adverse psychological impact on adolescents from regions with a low incidence of COVID-19. However, several adolescent groups had serious psychological complications and needed interventions in time. These adolescents included those at potential risk of exposure to COVID-19. Therefore, the strategy of closing schools should be implemented at early stage of pandemic to minimize the adverse psychological impact on adolescents.Funding Statement: This work was supported by the National Natural Science Foundation of China (Grant No.81573905) and program of National Clinical/Scientific Excellence in Chinese Medicine.Declaration of Interests: There are no conflicts of interest.Ethics Approval Statement: Our data collection protocol followed the American Association for Public Opinion Research (AAPOR) reporting guidelines, and was approved by the Ethics in Human Research Committee of the Third Affiliated Hospital of Beijing University of Chinese Medicine (No. BZYSY-2019KYKTPJ-21). We obtained informed consents from guardians before including participants in the study. The survey was anonymous and the information from the participants was confidential.

The production of antibodies for SARS-CoV-2 and its clinical implication (preprint)

Background: Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), a novel betacoronavirus, has caused an outburst of pneumonia cases in Wuhan, China. We report the production of specific IgM and IgG antibodies after the infection of SARS-CoV-2 and its implication for the diagnosis, pathology and the course of the disease as well as the recurrence of positive nucleic acid tests after discharge. Methods: Test results for SARS-CoV-2 IgM and IgG antibodies of 221 confirmed COVID-19 patients were retrospectively examined, and their clinical data were collected and analyzed based on various subgroups. SARS-CoV-2 IgM and IgG antibodies were determined with the chemiluminescence method. Findings: The concentration (S/CO) of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, with a median of 17.38 (IQR 4.39-36.4) for IgM and 5.59 (IQR 0.73-13.65) for IgG. Detection rates reached highest on day 16-18 and day 19-21 for IgM and IgG, which were 73.6% and 98.6%, respectively, with significantly higher concentration of IgG in critically ill patients than in those with mild to moderate disease (P=0.027). The concentration of the antibodies on day 16-21 is not correlated with the course or outcome of the disease (Spearman r < 0.20, P > 0.05). Nasopharyngeal swabs revealed positive SARS-CoV-2 RNA in up to 52.7% of recovered patients after discharge, whose IgG proved to be significantly lower than that of those with negative RNA results (P = 0.009). IgG and IgM were tested twice within 14 days after discharge with a 7-day interval, and the second testing of these antibodies displayed a decrease in concentration of 21.2% (IQR, 11.2%34.48%) for IgG and 23.05% (IQR, -27.96%46.13%) for IgM, without statistical significance between the patients with re-detectable positive RNA results and those with negative RNA results after discharge. However, those with positive results experienced a count decrease in lymphocyte subsets. Interpretation: The concentration of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, and antibody testing on day 16-21 is associated with increased detection rates, but the antibody concentration does not affect the course and outcome of the infection. Recovering patients with re-detectable positive SARS-CoV-2 RNA displayed lower concentration of IgG, but the downward trend of IgG during recovery indicated its limited duration of protection, and the protective effect of IgG remains to be investigated.