Status of 18 pediatric cases of COVID-19 post-liver transplantation.

We describe our experience with COVID-19 after pediatric liver transplantation (LT). In this study, we analyzed 18 of 196 children who contracted COVID-19 after LT during outpatient follow-up at our department. The severity of COVID-19 was mild in all cases, and all cases were cured without sequelae. COVID-19 after LT in children may have a high risk of severe disease. However, the disease is relatively mild and may be cured.Copyright © 2022 The Japan Society of Hepatology.

Status of 18 pediatric cases of COVID-19 post-liver transplantation

We describe our experience with COVID-19 after pediatric liver transplantation (LT). In this study, we analyzed 18 of 196 children who contracted COVID-19 after LT during outpatient follow-up at our department. The severity of COVID-19 was mild in all cases, and all cases were cured without sequelae. COVID-19 after LT in children may have a high risk of severe disease. However, the disease is relatively mild and may be cured. Copyright © 2022 The Japan Society of Hepatology.

Immersive Virtual Walking System Using an Avatar Robot

The ongoing COVID-19 pandemic has enforced governments across the world to impose social restrictions on the movement of people and confined them to their homes to avoid the spread of the disease. This not only forbids them from leaving their homes but also greatly reduces their physical activities. This situation has brought attention to virtual technologies such as virtual tours or telepresence robots. While these technologies allow people to remotely participate in activities, it does not address the problem of reduction in physical activities due to the pandemic. In this paper, we propose a telepresence robotic system driven by the user's gait to provide an immersive virtual walking experience in remote locations. To this end, we developed a control interface consisting of an automated treadmill that adjusts its speed to the user's pace automatically. This interface is used to control an avatar robot that sends a 360-degree live image back to the user for visual feedback. We conducted an evaluation experiment to compare the experience using the proposed system in two different conditions to that of regular walking. The results indicated that the proposed system gives an immersive and realistic virtual walking experience while demanding physical effort from the user. © 2022 IEEE.

Tempo Synchronization of Physical Activities with a Mixed-Reality Human-Machine-Interface

Physical trainers aid trainees to increase their motor learning of physical activities by providing multimodal feedback as well as adapting the training to their needs and progress. However, due to the fact that trainers are a scarce resource, added to the social distancing caused by the COVID19 pandemic, not many people have access to a trainer. In order to encourage people to continue practicing physical activities, this work presents a multimodal human-machine interface that automatically coaches ballroom dance. This is achieved by providing haptic, auditory, and visual feedback of the reference position and velocity trajectories, as well as its tempo. The proposed approach was tested in an experiment with 20 subjects. It was found out that subjects were able to reduce their position, velocity, and synchronization errors during and after the training, suggesting that users can retain the learned skills. Furthermore, we observed that higher performance is obtained at faster tempos.

Modality Influence on the Motor Learning of Ballroom Dance with a Mixed-Reality Human-Machine Interface

Mastering ballroom dance requires learning motor skills such as synchronizing the body motion to a tempo as well as memorizing long sequences of dance steps. Traditionally, the acquisition of these skills is guided by an instructor, who adapts the training to the level of the trainee. However, due to the measures that are taken globally against the COVID19, a great number of training facilities have partially or completely restricted access to their trainers. To facilitate the practice of ballroom dance without the need of a human instructor nor human contact, this paper presents a mixed-reality human-machine interface that provides part practice of ballroom dance. It achieves it by fractionalizing the dance into only the footwork and conveying the tempo, position trajectory, and velocity trajectory with multimodal feedback. The multimodal feedback is generated with a floor projection, vibrotactile actuators, and a metronome, which provide visual, haptic, and auditory feedback. In an experiment with 15 participants, results suggest that the motor learning of dance skills occurs when visual and haptic feedback is present, whereas it is further improved when the three modalities (visual, haptic, and auditory) are employed during training.

Inactivation of SARS-COV-2 by various surfactants

Introduction: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing the global pandemic is an enveloped virus and expected to be susceptible to some surfactants. The efficacy of the commercially available disinfectants and cleaners against this virus has been well examined so far, but only few reports mentioned about the efficacy of each surfactant alone. Objectives: This study aimed to evaluate the virucidal efficacy of various surfactants against SARS-CoV-2 (JPN/TY/WK-521). In addition, it also aimed to examine the presence of correlation between the virucidal efficacy and cytotoxicity of each surfactant. Methods: For this study, the experiments dealing with the novel coronavirus were carried out at the Research Institute for Microbial Diseases (Osaka University), while the cytotoxicity tests were performed at the Saraya Microbiologicial Research Center (Saraya Co., Ltd). The virucidal efficacy of each surfactant (cationic, anionic, amphoteric and non-ionic surfactant;0.01% ∼ 5.00%) was evaluated according to EN 14476 (dirty conditions). Their cytotoxicity was then examined by MTT assay. Results: The performance of EN 14476 with SARS-CoV-2 demonstrated that the cationic surfactant showed high virucidal efficacy. Although not as high as that of the cationic surfactant, some nonionic and amphoteric surfactants also showed relatively good virucidal efficacy, while the rest did not. After evaluation of cytotoxicity, a good correlation between the virucidal efficacy and the cytotoxicity of each surfactant was observed;the higher the cytotoxicity, the higher the virucidal efficacy. Conclusion: All of the tested cationic surfactants showed high virucidal efficacy and some nonionic and amphoteric surfactants had relatively highly virucidal efficacy. The evaluation of this strain has been finished. Further studies on the comparison of surfactant efficacy to other enveloped viruses with the original strain would bring some new insights to this research.