Highly Transparent Nanofibrous Membranes Used as Transparent Masks for Efficient PM0.3 Removal.

Currently, the quest for highly transparent and flexible fibrous membranes with robust mechanical characteristics, high breathability, and good filtration performance is rapidly rising because of their potential use in the fields of electronics, energy, environment, medical, and health. However, it is still an extremely challenging task to realize transparent fibrous membranes due to serious surface light reflection and internal light scattering. Here, we report the design and development of a simple and effective topological structure to create porous, breathable, and high visible light transmitting fibrous membranes (HLTFMs). The resultant HLTFMs exhibit good optical performance (up to 90% transmittance) and high porosities (>80%). The formation of such useful structure with high light transmittance has been revealed by electric field simulation, and the mechanism of fibrous membrane structure to achieve high light transmittance has been proposed. Moreover, transparent masks have been prepared to evaluate the filtration performance and analyze their feasibility to meet requirement of facial recognition systems. The prepared masks display high transparency (>80%), low pressure drop (<100 Pa) and high filtration efficiency (>90%). Furthermore, the person wearing this mask can be successfully identified by facial recognition systems. Therefore, this work provides an idea for the development of transparent, breathable, and high-performance fibrous membranes.

Beyond Sociodemographic and COVID-19-Related Factors: The Association Between the Need for Psychological and Information Support from School and Anxiety and Depression.

BACKGROUND In addition to sociodemographic and COVID-19- related factors, the needs of school support, including material, psychological and information support, have seldom been discussed as factors influencing anxiety and depression among college students during the COVID-19 pandemic. MATERIAL AND METHODS In this cross-sectional study, 3351 college students from China were surveyed through questionnaires about their sociodemographic and COVID-19 characteristics, the needs of school support, and their experiences with anxiety and depression. RESULTS Anxiety and depression were reported by 6.88% and 10.50% of students, respectively. Married, higher education, non-medical, and urban students had significantly higher risks of anxiety or depression. Additionally, symptoms such as cough and fever, especially when following a possible contact with suspected individuals, quarantine history of a personal contact, going out 1-3 times a week, not wearing a mask, and spending 2-3 hours browsing COVID-19-related information were significantly associated with the occurrence of anxiety or depression. Those who used methods to regulate their emotional state, used a psychological hotline, and who had visited a psychiatrist showed higher anxiety or depression. Those who used online curricula and books, used preventive methods for COVID-19, and who had real-time information about the epidemic situation of the school showed lower anxiety and depression. CONCLUSIONS In addition to sociodemographic and COVID-19-related aspects, students' needs for psychological assistance and information from schools were also associated with anxiety and depression among college students.

Robust Antibody and T Cell Responses in COVID-19 Patients Six Months After Infection (preprint)

Determining the longevity of natural immunity after SARS-CoV-2 infection is critical for understanding immune protection and optimizing vaccine design. Over six months have been passed since the emergence of COVID-19 in China. We evaluated humoral and cellular responses in 418 patients six months after infection. 95.9% and 98.1% of the patients maintained SARS-CoV-2-specific IgG and neutralizing antibodies. All severe patients were positive for IgG and neutralizing antibodies and had significantly higher titers than mild and moderate patients as well as asymptomatic individuals. The patients had a more robust SARS-CoV-2-specific CD4+ T cell response than CD8+ T cells six months after infection. Unexpectedly, sustained immune activation was observed, which displayed as the evaluated proinflammatory monocytes, non-classical NK cells, CD4+ Treg cells, and activated CD4+ T cells. Our findings indicate that SARS-CoV-2 gives rise to persisting and robust protective immunity, which provides a promising sign for prevention from reinfection and vaccination strategy.Funding: This work was supported by grants from the Natural Science Foundation of China (81773494 to M.J.M.), the National Major Project for Control and Prevention of Infectious Disease of China (2017ZX10303401-006 to M.J.M.), the Special National Project on Investigation of Basic Resources of China (2019FY101502 to M.J.M.).Conflict of Interest: The authors declare no competing interests.Ethical Approval: All patients provided written informed consent. The study was conducted following the Declaration of Helsinki, and the Institutional Review Board of the Academy of Military Medical Sciences approved the study protocol (IRB number: AF/SC-08/02.46).