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While the catalyst support layer enables the preparation of catalyst nanoparticles arrayed at high density, they are susceptible to instability in the catalyst activity lifetime due to surface and bulk diffusion mechanisms. This study proposes a strategy to mitigate this limitation by maintaining structural stability and thus chemical reactivity using a double-layer (DL) support architecture. In place of a single support layer, which cannot adequately perform two functions, i.e., inhibit subsurface diffusion and impede surface diffusion mechanisms, the DL support uses two distinct metal oxide layers to address each issue. The DL support is composed of a top "anchor layer" to impede surface diffusion mechanisms, such as Ostwald ripening, and a high crystallinity "sealing layer" to inhibit subsurface diffusion. Elucidation of the roles and requirements of each layer allowed for the generalization of this approach to alternative support material combinations. In this way, we demonstrated significant improvements in the stability and performance of the catalyst array. Furthermore, we demonstrated the growth of millimeter-tall single-walled carbon nanotube (SWNT) forests, suggesting the potential of DL supports for optimizing catalyst performance. [ABSTRACT FROM AUTHOR]

Background: The frequency and clinical profile of respiratory syncytial virus (RSV)–acute respiratory disease (ARD) in older adults in Japan has not been well‐characterized. Methods: This was a multicenter prospective observational cohort study to evaluate the occurrence rate of ARD in 1000 older adult participants (≥65 years) for 52 weeks during the 2019 to 2020 season. A multiplex polymerase chain reaction panel was used for pathogen detection in nasopharyngeal swab from participants diagnosed with ARD. Symptoms and impact of ARD was assessed using the Respiratory Infection Intensity and Impact Questionnaire (RiiQ™). The study was registered at UMIN (https://www.umin.ac.jp/ctr/): UMIN000037891. Results: RSV–ARD was detected in 24/1000 (2.4%) participants and RSV‐lower respiratory tract disease in 8/1000 (0.8%) participants. The median duration of RSV–ARD was 18 days. All 24 participants had utilized the medical services of outpatient visits and only 1 (4.2%) participant was hospitalized for RSV–ARD. The most common viruses other than RSV that caused ARD (detected in >10 participants) were human rhinovirus/enterovirus, parainfluenza 3, coronavirus OC43, human metapneumovirus, and influenza A/H1. The most frequent symptoms of RSV–ARD were cough, sore throat, nasal congestion, and expectoration. Conclusions: RSV was reported as a major pathogen for respiratory infections in older adults in Japan. [ABSTRACT FROM AUTHOR]

This study investigated the appropriate dose prescription method in static multi-beam stereotactic body radiotherapy for lung tumors. Static multi-beam stereotactic body radiotherapy is a mainstream treatment in Japan. Based on the hypothesis that dose prescription to lower isodose lines may improve planning target volume dose coverage and decrease doses to organs at risk, we investigated changes in dose-volume histograms with prescription to various isodose lines for planning target volume in static multi-beam stereotactic body radiotherapy. In all treatment plans, 45 Gy in 4 fractions were prescribed to 95% of the planning target volume. By adjusting the leaf margins of each beam, various prescription isodose lines encompassing 95% volume of the planning target volume were generated. The prescription isodose lines investigated were 40, 50, 60, 70, 80 and 90% lines relative to the maximum dose of each planning target volume. The conformity index, homogeneity index, mean lung dose, and V5-V40 of the lung were evaluated. The dose was calculated by the adaptive convolve algorithm. The conformity index was lowest in the 70% or 80% isodose plan. The mean lung doses and V10-V40 of the lung decreased steeply from the 90% to the 70% isodose plan, and was lowest in the 60% and 70% isodose plans. These indices increased in the 40% and 50% isodose plans. The optimal stereotactic body radiotherapy plans appeared to be dose prescription to the 60% or 70% isodose line. Further investigation is warranted to clarify the advantage of using this method clinically.