Key features of beach handball self-organization: comparison between genders

Serotonergic Axons as Fractional Brownian Motion Paths: Insights into the Self-organization of Regional Densities

10.1101/2019.12.27.889725 ◽

2019 ◽

Author(s):

Skirmantas Janušonis ◽

Nils Detering ◽

Ralf Metzler ◽

Thomas Vojta

Keyword(s):

Brownian Motion ◽

Fractional Brownian Motion ◽

Adult Brain ◽

The Self ◽

Self Organization ◽

Dense Matrix ◽

Two Dimensional ◽

Wide Range ◽

Motion Paths ◽

Key Features

ABSTRACTAll vertebrate brains contain a dense matrix of thin fibers that release serotonin (5-hydroxytryptamine), a neurotransmitter that modulates a wide range of neural, glial, and vascular processes. Perturbations in the density of this matrix have been associated with a number of mental disorders, including autism and depression, but its self-organization and plasticity remain poorly understood. We introduce a model based on reflected Fractional Brownian Motion (FBM), a rigorously defined stochastic process, and show that it recapitulates some key features of regional serotonergic fiber densities. Specifically, we use supercomputing simulations to model fibers as FBM-paths in two-dimensional brain-like domains and demonstrate that the resultant steady state distributions approximate the fiber distributions in physical brain sections immunostained for the serotonin transporter (a marker for serotonergic axons in the adult brain). We suggest that this framework can support predictive descriptions and manipulations of the serotonergic matrix and that it can be further extended to incorporate the detailed physical properties of the fibers and their environment.

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Patterns and pathways in nanoparticle self-organization

10.1093/oxfordhb/9780199533046.013.8 ◽

2017 ◽

Author(s):

MO Blunt ◽

A. Stannard ◽

E. Pauliac-Vaujour ◽

CP Martin ◽

Ioan Vancea ◽

...

Keyword(s):

Self Assembly ◽

Self Organization ◽

Nanoparticle Arrays ◽

Electron Conduction ◽

Self Organized ◽

Current Voltage ◽

Current Voltage Characteristics ◽

Key Features ◽

Nanoparticle Superlattices ◽

The Relationship

This article reviews relatively recent forms of self-assembly and self-organization that have demonstrated particular potential for the assembly of nanostructured matter, namely biorecognition and solvent-mediated dynamics. It first considers the key features of self-assembled and self-organized nanoparticle arrays, focusing on the self-assembly of nanoparticle superlattices, the use of biorecognition for nanoparticle assembly, and self-organizing nanoparticles. It then describes the mechanisms and pathways for charge transport in nanoparticle assemblies, with particular emphasis on the relationship between the current–voltage characteristics and the topology of the lattice. It also discusses single-electron conduction in nanoparticle films as well as pattern formation and self-organization in dewetting nanofluids.

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Exponential Self-Organization and Moore’s Law: Measures and Mechanisms

Complexity ◽

10.1155/2017/8170632 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Georgi Yordanov Georgiev ◽

Atanu Chatterjee ◽

Germano Iannacchione

Keyword(s):

Complex Systems ◽

Technological Progress ◽

Self Organization ◽

Logistic Growth ◽

Moore’S Law ◽

Moore's Law ◽

Energy Flows ◽

Physical Essence ◽

Key Features ◽

Self Organizing

The question of how complex systems become more organized and efficient with time is open. Examples are the formation of elementary particles from pure energy, the formation of atoms from particles, the formation of stars and galaxies, and the formation of molecules from atoms, of organisms, and of the society. In this sequence, order appears inside complex systems and randomness (entropy) is expelled to their surroundings. Key features of self-organizing systems are that they are open and they are far away from equilibrium, with increasing energy flows through them. This work searches for global measures of such self-organizing systems, which are predictable and do not depend on the substrate of the system studied. Our results will help to understand the existence of complex systems and mechanisms of self-organization. In part we also provide insights, in this work, about the underlying physical essence of Moore’s law and the multiple logistic growth observed in technological progress.

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Tissue self-organization underlies morphogenesis of the notochord

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2017.0320 ◽

2018 ◽

Vol 373 (1759) ◽

pp. 20170320 ◽

Cited By ~ 6

Author(s):

James Norman ◽

Emma L. Sorrell ◽

Yi Hu ◽

Vaishnavi Siripurapu ◽

Jamie Garcia ◽

...

Keyword(s):

Extracellular Matrix ◽

Aspect Ratio ◽

Physical Model ◽

Physical Models ◽

Self Organization ◽

Biological Structure ◽

Axis Elongation ◽

Key Features ◽

Vacuolated Cells ◽

Physical Principles

The notochord is a conserved axial structure that in vertebrates serves as a hydrostatic scaffold for embryonic axis elongation and, later on, for proper spine assembly. It consists of a core of large fluid-filled vacuolated cells surrounded by an epithelial sheath that is encased in extracellular matrix. During morphogenesis, the vacuolated cells inflate their vacuole and arrange in a stereotypical staircase pattern. We investigated the origin of this pattern and found that it can be achieved purely by simple physical principles. We are able to model the arrangement of vacuolated cells within the zebrafish notochord using a physical model composed of silicone tubes and water-absorbing polymer beads. The biological structure and the physical model can be accurately described by the theory developed for the packing of spheres and foams in cylinders. Our experiments with physical models and numerical simulations generated several predictions on key features of notochord organization that we documented and tested experimentally in zebrafish. Altogether, our data reveal that the organization of the vertebrate notochord is governed by the density of the osmotically swelling vacuolated cells and the aspect ratio of the notochord rod. We therefore conclude that self-organization underlies morphogenesis of the vertebrate notochord. This article is part of the Theo Murphy meeting issue on ‘Mechanics of development’.

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