561975 research outputs found
Sort by
Beam Tracing in Phase Space: Paraxial Description of High-Frequency Wave Beams in Turbulent Plasmas
No full text
Deletion of the moeA gene in Flavobacterium IR1 drives structural color shift from green to blue and alters polysaccharide metabolism
Get PDFStructural colors (SC), generated by light interacting with nanostructured materials, is responsible for the brightest and most vivid coloration in nature. Despite being widespread within the tree of life, there is little knowledge of the genes involved. Partial exceptions are some Flavobacteriia in which genes involved in a number of pathways, including gliding motility and polysaccharide metabolism, have been linked to SC. A previous genomic analysis of SC and non-SC bacteria suggested that the pterin pathway is involved in the organization of bacteria to form SC. Thus here, we focus on the moeA molybdopterin molybdenum transferase. When this gene was deleted from Flavobacterium IR1, the knock-out mutant showed a strong blue shift in SC of the colony, different from the green SC of the wild-type. The moeA mutant showed a particularly strong blue shift when grown on kappa-carrageenan and was upregulated for starch degradation. To further analyze the molecular changes, proteomic analysis was performed, showing the upregulation of various polysaccharide utilization loci, which supported the link between moeA and polysaccharide metabolism in SC. Overall, we demonstrated that single-gene mutations could change the optical properties of bacterial SC, which is unprecedented when compared to multicellular organisms where structural color is the result of several genes and can not yet be addressed genetically
Dynamic interplay of stress, meaning, social support, and autonomy in college students' mental health
No full textUnderstanding the impact of changes in perceived stress on mental health is critical for advancing targeted interventions; however, the psychological mechanisms underpinning these processes remain largely unexplored. Grounded in the Dual-Factor System of Mental Health (DFM) and Conservation of Resources (COR) theory, this study explores the intra-individual effects of changes in perceived stress on depression and flourishing, focusing on resources such as meaning in life, perceived social support, and individual autonomy. A total of 1,315 college students were surveyed during the COVID-19 college closures (T1) and subsequent reopening (T2). Latent Change Score Models revealed that only changes in perceived social support and individual autonomy served as protective mediators for changes in depression, while all resources contributed to changes in flourishing. Network analysis further supports the protective role of changes in perceived social support on depression and identifies changes in flourishing as central. These findings enhance our understanding of stress coping by capturing the detailed dynamics of both positive and negative dimensions, while providing actionable insights for developing context-specific resource interventions to address challenges in mental health
High-precision tracking of human foragers reveals adaptive social information use in the wild
No full textDynamic expression of laminB1during adult neurogenesis in the vertebrate brain
Get PDFBackground: In mammals, specific brain regions such as the dentate gyrus (DG) of the hippocampus and the subventricular zone (SVZ) of the lateral ventricles harbor adult neural stem/progenitor cells (ANSPCs) that give rise to new neurons and contribute to structural and functional brain plasticity. In contrast, other vertebrates such as salamanders and zebrafish exhibit a widely distributed neurogenic niches throughout the brain, suggesting a greater neurogenic capacity in adulthood. However, the mechanisms underlying this divergence in neurogenic potential among vertebrates remain elusive. To address this, we examined the expression dynamics of a critical epigenetic regulator for the long-term maintenance of murine ANSPCs, lamin B1, during adult neurogenesis across the vertebrate spectrum. Results: Lamin B1 expression patterns during adult neurogenesis are conserved among mammals including mouse, naked mole-rat, and ferret. However, these patterns differ between mammals and anamniotes. In mammals, neural stem cells and neuroblasts exhibited higher lamin B1 levels, and differentiated neurons possessed lower lamin B1 levels. On the other hand, anamniotes showed the opposite patterns of lamin B1 expression, with higher levels in neurons compared to stem cells. Conclusions: Our study shows that the lamin B1 expression pattern during adult neurogenesis differs between species, and that changes in lamin B1 protein sequence may contribute to the differences in lamin B1 expression patterns. This study highlights potential differences in cell-autonomous epigenetic regulation in the maintenance of ANSPC pools in the adult brain among species
Anle138b ameliorates pathological phenotypes in mouse and cellular models of Huntington's disease
No full textEinstein@Home All-sky “Bucket” Search for Continuous Gravitational Waves in LIGO O3a Public Data
Get PDFWe conduct an all-sky search for continuous gravitational waves using LIGO O3 public data from the Hanford and Livingston detectors. We search for nearly-monochromatic signals with frequencies and spin-down . We deploy this search on the Einstein@Home volunteer-computing project and on three super computer clusters; the Atlas supercomputer at the Max Planck Institute for Gravitational Physics, and the two high performance computing systems Raven and Viper at the Max Planck Computing and Data Facility. Our results are consistent with a non-detection. We set upper limits on the gravitational wave amplitude , and translate these to upper limits on the neutron star ellipticity and on the r-mode amplitude. The most stringent upper limits are at 173 Hz with , at the 90% confidence level
