We investigate the impact of confinement density (i.e., the number of individuals in a group per unit area of available space) on transitions from the polarized to milling state, using groups of rummy-nose tetra fish (Hemigrammus rhodostomus) under controlled experimental conditions. We demonstrate a continuous state transition controlled by confinement density in a group of live animals. During this transition, the school exhibits a bistable state, wherein both polarization and milling states coexist, with the group randomly alternating between them. A simple two-state Markov process describes the observed transition remarkably well. The confinement density influences the statistics of this bistability, shaping the distribution of transition times between states. Our findings suggest that confinement plays a crucial role in state transitions for moving animal groups. More generally, they provide an experimental benchmark for active matter models of macroscopic, self-propelled, confined agents.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1103/PhysRevE.110.034613 | DOI Listing |
Neurophotonics
January 2025
Washington University School of Medicine, Mallinckrodt Institute of Radiology, St. Louis, Missouri, United States.
Significance: Decoding naturalistic content from brain activity has important neuroscience and clinical implications. Information about visual scenes and intelligible speech has been decoded from cortical activity using functional magnetic resonance imaging (fMRI) and electrocorticography, but widespread applications are limited by the logistics of these technologies.
Aim: High-density diffuse optical tomography (HD-DOT) offers image quality approaching that of fMRI but with the silent, open scanning environment afforded by optical methods, thus opening the door to more naturalistic research and applications.
ACS Appl Mater Interfaces
January 2025
Key Laboratory of Luminescence and Optical Information, Beijing Jiaotong University, Ministry of Education, Beijing 100044, China.
Quasi-two-dimensional (quasi-2D) mixed-halide perovskites are a requisite for their applications in highly efficient blue perovskite light-emitting diodes (PeLEDs) owing to their strong quantum confinement effect and high exciton binding energy. The pace of quasi-2D blue PeLEDs is hindered primarily by two factors: challenges in precisely managing the phase distribution and defect-mediated nonradiative recombination losses. Herein, we utilize 2,2-diphenylethylamine (DPEA) with bulky steric hindrance to disturb the assembly process of a slender spacer host cation, 4-fluorophenylethylammonium (-F-PEA), enhancing phase distribution management in quasi-2D PeLEDs.
View Article and Find Full Text PDFACS Sens
January 2025
Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China.
It is crucial yet challenging to sensitively quantify low-abundance biomarkers in blood for early screening and diagnosis of various diseases. Herein, an analytical model of intra-mesopore immunoassay (IMIA) was proposed, which was competent to examine various biomarkers at the femtomolar level. The success is rooted in the design of an innovative superparamagnetic core-shell structure with FeO nanoparticles (NPs) at the core and hierarchically porous zeolitic imidazolate frameworks as a shell (FeO@HPZIF-8), achieved through a soft-template directed self-assembly coupled with confinement growth mechanism.
View Article and Find Full Text PDFMater Horiz
January 2025
Department of Applied Physics and Center for Computational Engineering and Sciences, State University of Campinas, Campinas, São Paulo, Brazil.
The recent synthesis of goldene, a 2D atomic monolayer of gold, has opened new avenues in exploring novel materials. However, the question of when multilayer goldene transitions into bulk gold remains unresolved. This study used density functional theory calculations to address this fundamental question.
View Article and Find Full Text PDFAdv Mater
January 2025
State Key Laboratory of Organic-Inorganic Composites and College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
The confining effect is essential to regulate the activity and stability of single-atom catalysts (SACs), but the universal fabrication of confined SACs is still a great challenge. Here, various lattice-confined Pt SACs supported by different carriers are constructed by a universal co-reduction approach. Notably, Pt single atoms confined in the lattice of Ni(OH) (Pt/Ni(OH)) with a high electron-deficient state exhibit excellent activity for basic hydrogen evolution reaction (HER).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!