We give strong analytic and numerical evidence that, under mild measurement assumptions, two qubits cannot both be recycled to generate Bell nonlocality between multiple independent observers on each side. This is surprising, as under the same assumptions it is possible to recycle just one of the qubits an arbitrarily large number of times [P. J. Brown and R. Colbeck, Phys. Rev. Lett. 125, 090401 (2020)]. We derive corresponding 'one-sided monogamy relations' that rule out two-sided recycling for a wide range of parameters, based on a general tradeoff relation between the strengths and maximum reversibilities of qubit measurements. We also show if the assumptions are relaxed to allow sufficiently biased measurement selections, then there is a narrow range of measurement strengths that allows two-sided recycling for two observers on each side, and propose an experimental test. Our methods may be readily applied to other types of quantum correlations, such as steering and entanglement, and hence to general information protocols involving sequential measurements.

Background: Numerous novel teaching methods have been developed in recent times for use in medical education. Of these methods, problem-based learning (PBL) and case-based learning (CBL) have attracted the most attention. We evaluated and compared the efficiency of these two teaching methods in dental education and discussed the importance of teachers to these courses. This study aims to evaluate the efficiency of PBL and CBL in dental education, and discuss the importance of teachers to the courses.Methods: In this study, 28 students enrolled in a seven-year program at the College of Stomatology at Shanghai Jiao Tong University were chosen as participants. In the fourth year, PBL combined with independent learning was used to teach students the theory of oral mucosal diseases. During the internship, CBL was used to present specific cases. Both methods were carried out with group discussion. After the PBL course, teachers assessed its effect by the students' class performance, their ability to collect data, and group cooperation. After the CBL course, its effect was assessed by the students' ability in history-taking, diagnosis and antidiastole, and case analysis. In addition, the teachers' roles in both methods were assessed by both the students and the teachers themselves. Data was collected by questionnaire survey and statistically analyzed with SPSS Statistics 20.Results: PBL significantly improved students' self-learning abilities in the theory course. CBL helped students make diagnoses and develop treatment plans for actual cases in the internship. Both students and teachers thought that teachers were indispensable to both PBL and CBL. There was no difference between student and teacher views.Conclusions: Although PBL and CBL have different focuses, their combination may enhance teaching effectiveness in dental education. Additionally, teachers play an important role in the application of both these teaching methods.

Although it is undeniable that the COVID-19 pandemic presented new threats and traumas for human beings, posttraumatic growth that took place after the struggle with this highly challenging crisis cannot be ignored. Therefore, based on the posttraumatic growth theory, the present research focuses on aspects of tourists' positive changes after the COVID-19 outbreak. A total of 1165 potential tourists from 197 cities in 31 provinces of China were analyzed using symmetrical and asymmetrical approaches. The results of the partial least squares test revealed the net effects of social support, psychological distress, and infection risk perception on the three dimensions of tourists’ posttraumatic growth, namely, travel risk aversion, social identity, and altruistic behavior. Fuzzy-set qualitative comparative analysis provided causal recipes for realizing posttraumatic growth, and necessary condition analysis supplemented the necessary antecedents. The implications of the findings and the paths for future research are also presented.

The present research aims to explore the perceived destination personality of the Larong Wuming Buddhist Academy, a site that is a pilgrimage destination in the Tibetan region of China, and to examine the influence of involvement as an antecedent on the destination personality. This study further investigates the direct and indirect impact of a destination personality on loyalty. A total of 2454 online travel reviews and a convenience sample of 348 usable surveys were analyzed. The personalities of the pilgrimage destination in three specific dimensions were revealed, namely, the religious, agreeable, and ethereal dimensions. The findings verified the positive effect of tourist involvement on the pilgrimage destination personality. Furthermore, in the context of a pilgrimage, the mediating role of self-congruity and satisfaction between the destination personality and loyalty has been confirmed.

Objective: This study aimed to evaluate the effect of a femtosecond laser on the osteogenetic efficiency of polyetheretherketone (PEEK) and its composite for clinical applications. Methods: One hundred pieces of PEEK and its composite (6 × 4 × 2 mm3) were randomly divided into four groups and treated as follows: group A1, PEEK; group A2, PEEK + femtosecond laser; group B1, PEEK composite; and group B2, PEEK composite + femtosecond. The surface morphology of the pieces of each group was observed through scanning electron microscopy. The surface roughness and wettability, which were considered as the main parameters affecting cell adhesion characteristics of implants, were measured. The animals whose mandibles were implanted with the four groups of materials were killed at the end of 6 and 12 weeks. Various characterization tests, such as Cone Beam Computed Tomography (CBCT), push-out test, microscope test, and bone implant contact , were conducted to investigate the healing effect between materials and bones. Results: In group B1, the nanoparticles in PEEK were uniformly distributed. In groups A2 and B2, many periodic nanostructures were observed. The surface roughness and wettability of group B2 were significantly increased compared to those of the other groups ( p < 0.05). At each time point, the number of trabecular bones, contact strength, and BIC of group B2 were higher than those of the three other groups ( p < 0.05). Compared with those of group A1, the test results of group B1 were significantly improved. Conclusion: Femtosecond lasers can effectively enhance the biological activity of PEEK and its composite; PEEK composite exhibits better biological activity than PEEK.

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This study concerns a simulation and optimisation of the personnel evacuation modelling of a shopping mall in Weiyang District, Xi’an. First, investigations were conducted to determine the human flow rate tand occupant distribution during the rush hours to builda queuing theory model. Then, a simulation was implemented with an evacuation simulation software Pathfinder, followed by an analysis to the evacuation status and bottlenecks. On the basis of the evacuation status, proposals were put forward on how to overcome the bottlenecks to achieve the optimal matching among the personnel, emergency staircases and aisles. Finally, the improved scheme was simulated. Compared with time taken by the evavuation before improvement, the time taken was greatly shortened after improvement, proving the feasibility of the scheme. Through the simulation experimentaiton, it was found that ecacuation modelling can greatly facilitate reseaches on the evacuation problems in multistoryed shopping malls.