ABSTRACT
In order to counteract the COVID-19 pandemic by wearing face masks, we examine washable fabric-based triboelectric nanogenerators (FTENGs). We applied the flash-spun nonwoven fabric (FS fabric) into the FTENGs, comparing the melt-blown nonwoven fabric (MB fabric) based FTENGs, which is conventionally studied in the field of energy harvesting. For reusability, all our proposed FTENGs are systematically investigated by controlling the washing conditions. After washing, the degradation ratio of the obtained output voltage is found to be only 12.5% for FS FTENGs, compared to the ratio of about 50% for the typical MB FTENGs. A rather small degradation ratio for FS fabric cases has resulted from less changed fabric structure after washing due to more dense fabric nature. Additionally, in order to improve the electrical characteristics of FS FTENGs. Note that the output voltage of FTENGs exhibits as much as 600 V.
ABSTRACT
The coronavirus disease 2019 (COVID-19) outbreak became a worldwide pandemic in 2020. Social distancing measures, such as self-quarantine, lockdowns, and school closures, which have proven efficacy in various pandemic situations, remain in use in Korea. These measures prevented viral transmission to some extent; however, adverse effects have also resulted. First, the negative effect of social isolation on mental health is evident. This influences the psychiatric milieu of parents and children directly and indirectly. The most stressful factor among Korean youth was the restriction of outdoor activities. Increasing parenting burden result in increased screen time among youth, and social isolation created depressive mood with symptoms similar to those of attention deficit hyperactivity disorder and anxiety. Second, symptoms of posttraumatic stress disorder (PTSD) and somatization are prevalent among children and adolescents. The sense of threatened health and life during the pandemic, one symptom of PTSD, is a strong risk factor for somatization. Finally, the increased pattern of child abuse in pandemic indicates increased levels of emotional/psychological abuse and nonmedical neglect. Social isolation makes people less aware of these events. Because pediatricians evaluate pediatric patients and their families, they should regularly assess emotional/stress factors, especially when somatization is prominent during the pandemic, and cautiously recommend that families seek advice from mental health professionals when warranted. Primary physicians must understand the characteristics and aspects of child abuse in the COVID-19 pandemic, make efforts to identify signs of child abuse, and deliver accurate information and preventive strategies for child abuse to caregivers, thereby functioning as a professional guardian. To promote the mental health of parents and children during the COVID-19 pandemic, more research and cooperation among health professionals, families, governments, and schools are needed in the future.
ABSTRACT
Antibiotic therapy is the gold standard for bacterial infections treatment. However, the rapid increase in multidrug-resistant (MDR) bacterial infections and its recent use for secondary bacterial infections in many COVID-19 patients has considerably weakened its treatment efficacy. These shortcomings motivated researchers to develop new antibacterial materials, such as nanoparticle-based antibacterial platform with the ability to increase the chances of killing MDR strains and prevent their drug resistance. Herein, we report a new black phosphorus (BP)-based non-damaging near-infrared light-responsive platform conjugated with ZnO and Au nanoparticles as a synergistic antibacterial agent against Staphylococcus aureus species. First, BP nanosheets containing Au nanoparticles were assembled in situ with the ZnO nanoparticles prepared by a low-temperature solution synthesis method. Subsequently, the antibacterial activities of the resulting Au-ZnO-BP nanocomposite against the non-resistant, methicillin-resistant, and erythromycin-resistant S. aureus species were determined, after its photothermal efficacy was assessed. The synthesized nanocomposite exhibited excellent anti-S. aureus activity and good photothermal characteristics. The non-resistant S. aureus species did not produce drug-resistant bacteria after the treatment of multiple consecutive passages under the pressure of the proposed nanoantibiotic, but rapidly developed resistance to erythromycin. This work clearly demonstrates the excellent photothermal antibacterial properties of Au-ZnO-BP nanocomposite against the MDR S. aureus species.