Research on solid shell element based on penalty method.

Since the angle degrees of freedom do not have the vector property, it is critical to handle this for nonlinear geometrical behavior. To simulate the nonlinear geometrical behavior of shell structure efficiently, we developed a solid-shell element type without drilling degrees of freedom. In this paper, the element satisfies the assumption of the straight normal of the shell and we established penalty functions in the thickness direction of the shell. The formulations of equivalent node force and tangent stiffness obtained by 3D isoparametric element theory can be expressed by matrix forms clearly. The constitutive relationship in the global system is derived from the local constitutive matrix according to the tensor coordinate transform. Finally, taking a series of classic flat plate problems and curved shell problems as examples, the solid shell element using the penalty method is compared with the solid shell element using the artificial stiffness method and other shell elements. The results show that the solid element proposed in this paper can effectively eliminate shear self-locking after using the reduced integral scheme and obtain satisfactory accuracy for thin shells and medium-thickness•A type of solid shell element without rotational degrees of freedom is introduced using the penalty method.•A suitable penalty factor of this element is determined through numerical experiments.•This element is more efficient than the traditional shell elements and can be programmed with less time.

Reopening International Borders without Quarantine: Contact Tracing Integrated Policy against COVID-19

With the COVID-19 vaccination widely implemented in most countries, propelled by the need to revive the tourism economy, there is a growing prospect for relieving the social distancing regulation and reopening borders in tourism-oriented countries and regions. The need incentivizes stakeholders to develop border control strategies that fully evaluate health risks if mandatory quarantines are lifted. In this study, we have employed a computational approach to investigate the contact tracing integrated policy in different border reopening scenarios in Hong Kong, China. Built on a modified SEIR epidemic model with a 30% vaccination coverage, the results suggest that scenarios with digital contact tracing and quick isolation intervention can reduce the infectious population by 92.11% compared to those without contact tracing. By further restricting the inbound population with a 10,000 daily quota and applying moderate-to-strong community non-pharmacological interventions (NPIs), the average daily confirmed cases in the forecast period of 60 days can be well controlled at around 9 per day (95% CI: 7-12). Two main policy recommendations are drawn from the study. First, digital contact tracing would be an effective countermeasure for reducing local virus spread, especially when it is applied along with a moderate level of vaccination coverage. Second, implementing a daily quota on inbound travelers and restrictive community NPIs would further keep the local infection under control. This study offers scientific evidence and prospective guidance for developing and instituting plans to lift mandatory border control policies in preparing for the global economic recovery.

Consumer Response to Corporate Hypocrisy From the Perspective of Expectation Confirmation Theory.

Based on the concept of hypocrisy perception, this paper studies and discusses consumers' response to corporate social responsibility (CSR) hypocrisy perception, discusses the formation of consumers' hypocrisy perception from the perspective of consumers' expectation of CSR, and originally reveals the psychological and behavioral mechanisms of the generation of negative emotions and their role in consumer response. The results are as follows: (1) consumers' CSR expectations and CSR perceived performance have a significant impact on their perception of hypocrisy; (2) consumers' perception of hypocrisy has a significant impact on their negative emotions; (3) consumers' negative emotions can have a significant impact on their attitudes and negative behaviors. The research results show that consumers' expectations of CSR activities can affect consumers' attitudes and behaviors, among which consumers' perceived CSR performance, perceived hypocrisy, and negative emotions play an important role. In the implementation of CSR activities, enterprises should avoid making consumers have excessive expectations and appease their negative emotions, so as to improve the implementation effect of CSR activities.

Analysis of the genetic stability of the master virus seeds for live attenuated influenza vaccine produc-tion / 中华微生物学和免疫学杂志

Objective To analyze the genetic stability of master virus seed lots of live attenuated influenza vaccineA/17/California/2009/38(H1N1)andA/17/Perth/09/87(H3N2)strains.Methods The master virus seed lots were inoculated into chicken eggs for subculture.The complete genome of the 2nd, 3rd, 5th and 10th generations of viruses were amplified and sequenced.The genes encoding hemagglu-tinin ( HA) and neuraminidase ( NA) were compared with those of the WHO recommended circulating wild-type virus strains used for vaccine production in northern hemisphere during 2011-2012 influenza season.Six internal genes (PB2, PB1, PA, NP, M and NS) of each virus generation were compared with their master donor virus strain (A/Leningrad/134/17/57) for the evaluation of the genetic stability.Results The muta-tion rates of H1N1 and H3N2 strains after 10 passages were 0.035%and 0.022%, respectively.No muta-tions were found at the critical sites for controling thecold adapted ( ca) , temperature sensitive ( ts) and at-tenuated ( att) phenotypes.Conclusion The live attenuated influenza vaccine strains possessed high genet-ic stability as their tenth generations still shared 99% of homology with the original seed lots.All of the working virus seed lots met the requirements of Pharmacopoeia of the People′s Republic of China ( 2010 edition) .