CHANGES IN THE WORKERS' PERCEPTION OF WORKING FROM OFFICE IN THE WAKE OF COVID-19 A survey of office workers and teleworkers

The authors conducted an online survey in Japan in March 2019 (N=2,684) to gather feedback from workers who commute to their offices and work with several people in a corporate environment. However, considering the COVID-19 pandemic changed our workstyle, a second survey (n=490) was conducted in December 2020 for workers whose offices remained mostly unchanged since the last survey to compare data from both surveys for the same respondents and investigate the changes in the value of office spaces. The result suggested that the survey respondents were influenced by the changes in workstyles and attitudes in the telework experience. © 2022 Architectural Institute of Japan. All rights reserved.

Factors Associated with Injuries and Gender Differences in Japanese Adolescent Athletes Returning to Sports Following the COVID-19 Restriction

Background: Because the worldwide spread of coronavirus disease 2019 has forced a moratorium on student sports activity in Japan, reports on its impact on sports injuries are limited given its novelty. This study aimed to determine the characteristics and gender differences of injuries in adolescent athletes after returning to sport following restriction of club activities due to the coronavirus pandemic. Methods: An online retrospective questionnaire was distributed to 500 adolescent athletes who belong to school sports clubs in Japan from March 1–19, 2021. An anonymous questionnaire was created before and after the restriction of sports activities following the declaration of the first state of emergency of the COVID-19 pandemic in Japan. Subsequently, 258 valid responses were obtained, and injury-related characteristics were compared between injured and non-injured athletes after returning to sports and between genders for injured athletes. There were no differences in the body areas of sports injuries between males and females. Result: We found that injury experience before club activity restriction was significantly associated with injury after returning to sports (p < 0.001). Moreover, practice time increased before and after the restriction in the injury group (p = 0.038). The injury rate was higher in females (p < 0.024), and the trauma rate was higher among males (p = 0.016). There were no differences in the body areas of sports injuries between males and females. Conclusions: Our results provide gender-differentiated ideas and suggestions as they relate to injury prevention once in adolescent athletes returning to sports after the coronavirus disease 2019 induced restriction of club activities. We show the need for injury rehabilitation and practice time control in adolescent athletes in the coronavirus disease 2019 setting.

External Quantum Efficiency of 6.5% at 300 nm Emission and 4.7% at 310 nm Emission on Bare Wafer of AlGaN-Based UVB LEDs

As per the Minamata Convention on Mercury, regulation on mercury use will be stricter from the year of 2020, and safe AlGaN-based ultraviolet (UV) light sources are urgently needed for killing SARS-CoV-2 (corona virus). AlGaN-based ultraviolet-B (UVB) light-emitting diodes (LEDs) and UVB laser diodes (LDs) have the potential to replace toxic mercury UV lamps. Previously, the internal-quantum-efficiency (ηint) was enhanced from 47 to 54% in AlGaN UVB multiquantum wells (MQWs). However, some nonlinear behaviors in both light output power (L) and external quantum efficiency (ηext) in the 310 nm band UVB LEDs were observed, and later on, such nonlinearities were overcome by reducing the thicknesses of quantum well barriers (TQWB) in MQWs. After relaxing the n-AlGaN electron injection layer up to 50% underneath the MQWs and using a highly reflective Ni/Al p-electrode, L and ηext of the 310 nm band UVB LED were greatly improved from 12 mW and 2.3% to record values of 29 mW and 4.7%, respectively. Similarly, for the 294 nm band UVB LED, ηext and L values, respectively, were also remarkably improved up to 6.5% and 32 mW at room temperature under bare wafer conditions using a better carrier confinement scheme in the MQWs as well as using a moderately Mg-doped p-type multiquantum-barrier electron-blocking layer (p-MQB EBL). The moderately doped p-MQB EBL was used to achieve better hole transport to enhance the hole injection toward the MQWs as well as to block the high-energy electron from overshooting. Possible explanations and recommendations for the improvements in the performances of 294-310 nm UVB LEDs are broadly discussed. Most importantly, such controllable multi-UVB-wavelength emitters may extend nitride-based LEDs to previously inaccessible areas, for example, electrically pumped AlGaN-based UVB LDs. © 2020 American Chemical Society.