Integration of sensory and molecular inputs from the environment shapes animal behavior. A major site of exposure to environmental molecules is the gastrointestinal tract, where dietary components are chemically transformed by the microbiota 1 and gut-derived metabolites are disseminated to all organs, including the brain 2 . In mice, the gut microbiota impacts behavior 3 , modulates neurotransmitter production in the gut and brain 4,5 , and influences brain development and myelination patterns 6,7 . Mechanisms mediating gut-brain interactions remain poorly defined, though broadly involve humoral or neuronal connections. We previously reported that levels of the microbial metabolite 4-ethylphenyl sulfate (4EPS) were elevated in a mouse model of atypical neurodevelopment 8 . Herein, we identified biosynthetic genes from the gut microbiome that mediate conversion of dietary tyrosine to 4-ethylphenol (4EP), and bioengineered gut bacteria to selectively produce 4EPS in mice. 4EPS entered the brain and was associated with changes in region-specific activity and functional connectivity. Gene expression signatures revealed altered oligodendrocyte function in the brain, and 4EPS impaired oligodendrocyte maturation in mice as well as decreased oligodendrocyte-neuron interactions in ex vivo brain cultures. Mice colonized with 4EP-producing bacteria exhibited reduced myelination of neuronal axons. Altered myelination dynamics in the brain have been associated with behavioral outcomes 7,[9][10][11][12][13][14]13,14 . Accordingly, we observed that mice exposed to 4EPS displayed anxiety-like behaviors, and pharmacologic treatments that promote oligodendrocyte differentiation prevented the behavioral effects of 4EPS. These findings reveal that a gut-derived molecule influences complex behaviors in mice via effects on oligodendrocyte function and myelin patterning in the brain.
Purpose Knowledge sharing usually happens in a work group context, but it is rarely know how group leaders influence their members’ knowledge-sharing performance. Based on social exchange theory (SET) and the perspective of positive organizational behavior (POB), this study aims to argue that a group leader’s positive leadership (e.g. empowering leadership) can help group members develop positive psychological capital which can increase their knowledge sharing. Design/methodology/approach The authors conduct a multilevel analysis to explore the interrelationship among empowering leadership, psychological capital and knowledge sharing. The sample includes 64 work groups consisting of 537 group members, and empirical testing is carried out by hierarchical linear modeling. Findings The results show that empowering leadership in a work group has a direct cross-level impact on members’ knowledge sharing and that psychological capital partially mediates the relationship between empowering leadership and knowledge sharing. As a result, this study shows that group leaders with positive leadership can help their members develop better positive psychological resources, which should lead to better knowledge sharing. Originality/value Based on the multilevel perspective and SET, this is the first study to explore how group leaders’ empowering leadership influences members’knowledge sharing. Depending on integrating the POB perspective into SET, this study is also the first one that connects two emerging and important research issues – POB and knowledge sharing.
High density metal cross bars at 17 nm half-pitch were fabricated by nanoimprint lithography. Utilizing the superlattice nanowire pattern transfer technique, a 300-layer GaAs/AlGaAs superlattice was employed to produce an array of 150 Si nanowires (15 nm wide at 34 nm pitch) as an imprinting mold. A successful reproduction of the Si nanowire pattern was demonstrated. Furthermore, a cross-bar platinum nanowire array with a cell density of approximately 100 Gbit/cm(2) was fabricated by two consecutive imprinting processes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.