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Cells that reside within a community can cooperate and also compete with each other for resources. It remains unclear how these opposing interactions are resolved at the population level. Here we investigate such an internal conflict within a microbial (Bacillus subtilis) biofilm community: cells in the biofilm periphery not only protect interior cells from external attack but also starve them through nutrient consumption. We discover that this conflict between protection and starvation is resolved through emergence of long-range metabolic co-dependence between peripheral and interior cells. As a result, biofilm growth halts periodically, increasing nutrient availability for the sheltered interior cells. We show that this collective oscillation in biofilm growth benefits the community in the event of a chemical attack. These findings indicate that oscillations support population-level conflict resolution by coordinating competing metabolic demands in space and time, suggesting new strategies to control biofilm growth., Cooperation and competition are complex social interactions that can have critical roles in biological communities. Cooperative behaviour often increases the overall fitness of the population through processes such as division [...]

Abstract Invariant natural killer T (iNKT) cells are a subset of T cells that are characterized by a restricted T-cell receptor (TCR) repertoire and a unique ability to recognize glycolipid antigens. These cells are found in all tissues, and evidence to date suggests that they play many immunological roles in both homeostasis and inflammatory conditions. The latter include lung inflammatory diseases such as asthma and infections: the roles of lung-resident iNKT cells in these diseases have been extensively researched. Here, we provide insights into the biology of iNKT cells in health and disease, with a particular focus on the role of pulmonary iNKT cells in airway inflammation and other lung diseases.

This study aimed to evaluate the effectiveness of wireless emergency alerts (WEAs) on social distancing policy. The Republic of Korea has been providing information to the public through WEAs using mobile phones. This study used five data sets: WEA messages, news articles including the keyword "COVID-19," the number of confirmed COVID-19 patients, public foot traffic data, and the government's social distancing level. The WEAs were classified into two topics-"warning" and "guidance"-using a random forest model. The results of the correlation analysis and further detailed analysis confirmed that the "warning" WEA topic and number of news articles significantly affected public foot traffic. However, the "guidance" topic was not significantly associated with public foot traffic. In general, the Korean government's WEAs were effective at encouraging the public to follow social distance recommendations during the COVID-19 pandemic. In particular, the "warning" WEA topic, by providing information about the relative risk directly concerning the recipients, was significantly more effective than the "guidance" topic., (© 2022. The Author(s).)

Here we report the highest energy conversion efficiency and good stability of PbS thin film-based depleted heterojunction solar cells, not involving PbS quantum dots. The PbS thin films were grown by the low cost chemical bath deposition (CBD) process at relatively low temperatures. Compared to the quantum dot solar cells which require critical and multistep complex procedures for surface passivation, the present approach, leveraging the facile modulation of the optoelectronic properties of the PbS films by the CBD process, offers a simpler route for optimization of PbS-based solar cells. Through an architectural modification, wherein two band-aligned junctions are stacked without any intervening layers, an enhancement of conversion efficiency by as much as 30% from 3.10 to 4.03% facilitated by absorption of a wider range of solar spectrum has been obtained. As an added advantage of the low band gap PbS stacked over a wide gap PbS, the devices show stability over a period of 10 days.

Purpose: To evaluate the effects of different methods of head elevation on intraocular pressure (IOP) in healthy young subjects., Methods: Twenty-four healthy young Korean subjects were included in this prospective observational study. The IOP measurements were taken with the subjects in the sitting position and in the supine positions with the head flat and 30° up using two different methods: (1) raising the bed head and (2) using multiple pillows. IOP was measured using Tonopen AVIA in both eyes 10 min after assuming each position in a randomized sequence. The Wilcoxon signed-rank test was used to compare the IOP by changing the methods of head elevation., Results: Mean IOP of both eyes when sitting was lower than that measured in the supine position with head flat (P=0.001). Compared with that measured in the supine position with head flat, the mean IOP was lower when measured in the supine position with the head kept 30 ° up by bed head elevation (P=0.001), whereas the mean IOP was not significantly different when measured in the supine position with the head elevated using multiple pillows (right eye, P=0.061; left eye, P=0.089)., Conclusion: In normal subjects, IOP was lower when measured in the supine position with the head kept up by the bed head elevation compared with that measured when lying flat. However, such head-up position-induced IOP reduction was not found when the head was kept up using multiple pillows. These findings suggest that elevating the head using multiple pillows may not help to reduce IOP in the supine posture.