Example Of Self-organization Research Articles

Selective decision-making and collective behavior of fish by the motion of visual attention.

Collective motion provides a spectacular example of self-organization in Nature. Visual information plays a crucial role among various types of information in determining interactions. Recently, experiments have revealed that organisms such as fish and insects selectively utilize a portion, rather than the entirety, of visual information. Here, focusing on fish, we propose an agent-based model where the direction of attention is guided by visual stimuli received from the images of nearby fish. Our model reproduces a branching phenomenon where a fish selectively follows a specific individual as the distance between two or three nearby fish increases. Furthermore, our model replicates various patterns of collective motion in a group of agents, such as vortex, polarized school, swarm, and turning. We also discuss the topological nature of the visual interaction, as well as the positional distribution of nearby fish and the map of pairwise and three-body interactions induced by them. Through a comprehensive comparison with existing experimental results, we clarify the roles of visual interactions and issues to be resolved by other forms of interactions.

Substrate evaporation drives collective construction in termites.

Termites build complex nests which are an impressive example of self-organization. We know that the coordinated actions involved in the construction of these nests by multiple individuals are primarily mediated by signals and cues embedded in the structure of the nest itself. However, to date there is still no scientific consensus about the nature of the stimuli that guide termite construction, and how they are sensed by termites. In order to address these questions, we studied the early building behavior of Coptotermes gestroi termites in artificial arenas, decorated with topographic cues to stimulate construction. Pellet collections were evenly distributed across the experimental setup, compatible with a collection mechanism that is not affected by local topography, but only by the distribution of termite occupancy (termites pick pellets at the positions where they are). Conversely, pellet depositions were concentrated at locations of high surface curvature and at the boundaries between different types of substrate. The single feature shared by all pellet deposition regions was that they correspond to local maxima in the evaporation flux. We can show analytically and we confirm experimentally that evaporation flux is directly proportional to the local curvature of nest surfaces. Taken together, our results indicate that surface curvature is sufficient to organize termite building activity and that termites likely sense curvature indirectly through substrate evaporation. Our findings reconcile the apparently discordant results of previous studies.

Substrate evaporation drives collective construction in termites

Termites build complex nests which are an impressive example of self-organization. We know that the coordinated actions involved in the construction of these nests by multiple individuals are primarily mediated by signals and cues embedded in the structure of the nest itself. However, to date there is still no scientific consensus about the nature of the stimuli that guide termite construction, and how they are sensed by termites. In order to address these questions, we studied the early building behavior of Coptotermes gestroi termites in artificial arenas, decorated with topographic cues to stimulate construction. Pellet collections were evenly distributed across the experimental setup, compatible with a collection mechanism that is not affected by local topography, but only by the distribution of termite occupancy (termites pick pellets at the positions where they are). Conversely, pellet depositions were concentrated at locations of high surface curvature and at the boundaries between different types of substrate. The single feature shared by all pellet deposition regions was that they correspond to local maxima in the evaporation flux. We can show analytically and we confirm experimentally that evaporation flux is directly proportional to the local curvature of nest surfaces. Taken together, our results indicate that surface curvature is sufficient to organize termite building activity and that termites likely sense curvature indirectly through substrate evaporation. Our findings reconcile the apparently discordant results of previous studies.

Formation of Precipitation Ellipsoidal Disks and Spheres in the Wake of a Planar Diffusion Front.

Pattern formation is one of the examples of self-organization. In the generation of patterns, the coupling between the mass transport of the chemical species and their chemical reactions plays an important role. Periodic precipitation (Liesegang phenomenon) is a type of pattern formation in which layered precipitation structures form in the wake of the diffusion front. Here, we show a new type of precipitation pattern formation in zeolitic imidazolate framework-67 in a solid hydrogel column in a test tube manifested in the generation of precipitation ellipsoidal disks and spheres in the wake of the planar diffusion front of the outer electrolyte (2-methylimidazole). To increase the probability of the emergence of ellipsoidal disks and spheres, the surfaces of the borosilicate test tubes were chemically treated and functionalized. To support the experimental findings, we developed a reaction-diffusion model that qualitatively describes the formation of precipitate ellipsoidal disks and spheres in a test tube.

Collective behavior and self-organization in neural rosette morphogenesis.

Neural rosettes develop from the self-organization of differentiating human pluripotent stem cells. This process mimics the emergence of the embryonic central nervous system primordium, i.e., the neural tube, whose formation is under close investigation as errors during such process result in severe diseases like spina bifida and anencephaly. While neural tube formation is recognized as an example of self-organization, we still do not understand the fundamental mechanisms guiding the process. Here, we discuss the different theoretical frameworks that have been proposed to explain self-organization in morphogenesis. We show that an explanation based exclusively on stem cell differentiation cannot describe the emergence of spatial organization, and an explanation based on patterning models cannot explain how different groups of cells can collectively migrate and produce the mechanical transformations required to generate the neural tube. We conclude that neural rosette development is a relevant experimental 2D in-vitro model of morphogenesis because it is a multi-scale self-organization process that involves both cell differentiation and tissue development. Ultimately, to understand rosette formation, we first need to fully understand the complex interplay between growth, migration, cytoarchitecture organization, and cell type evolution.

Chamber Ensemble Named After Ignacy Feliks Dobrzyński: 20 Years of SocioCultural Communication

The relevance of the study. Problems of socio-cultural communication in music art are of highest relevance in sociology and music studies, especially, during the war, when it is necessary to preserve all cultural assets of the country.
 The purpose of the article: to trace stages of formation and activity of honoured collective representative of Polish culture – Chamber ensemble named after Ignacy Feliks Dobrzyński of social organization Zhytomyr Regional Association of the Poles of Ukraine in the beginning of the XXIst century and had been actively concertizing before the very beginning of the “great war” (February 2022).
 In order to achieve the said purpose the following methods were used:
 
 of culture studies (historical-genetic, historical-dynamic, comparative);
 of sociology of music (sociological observation);
 communicative music studies (content analysis, discourse analysis, functional-communicative);
 of theory of performing (historical-stylistic, genre, interpretation).
 
 Problem statement. Activity of the ensemble for 20 years has been covered in newspapers, magazines, sites of Zhytomyr Regional Union of the Poles of Ukraine, social networks, TV shows “Slovo polske” [The Polish Word] and “Poliaky Zhytomyrshchyny” [The Poles of Zhytomyr land]. Mostly in genre of announcements, reviews, feedback of listeners.
 History of the ensemble and professional assessment of its creative work and social activities became actual only with awareness that important cultural phenomena can exist not only in the capital, but in province as well.
 Scientific novelty. Distinctive features of the Chamber ensemble named after Ignacy Feliks Dobrzyński as subject of research is duration and cultural edifying and educational nature of its functioning. Suggested research is the first attempt to trace activity of this group in the said aspect.
 Statement of basic material. The article reviews activity of the ensemble starting from its creation at the late XX and early XXI centuries until the last concert that took place before the “great war”.
 We have distinguished main spheres of its activity: performing music composers of Volyn-Zhytomyr land; revival of traditions of Catholic Church concerts; social and educational activity.
 Conclusions and directions for future research. Chamber ensemble named after Ignacy Feliks Dobrzyński is a rather rare example of self-organization of the collective ideologically motivated. The research perspective could be monography about its activity.

Universality of breath figures on two-dimensional surfaces: An experimental study

Droplet condensation on surfaces produces patterns, called breath figures. Their evolution into self-similar structures is a classical example of self-organization. It is described by a scaling theory with scaling functions whose universality has recently been challenged by numerical work. Here, we provide thorough experimental testing, where we inspect substrates with vastly different chemical properties, stiffness, and condensation rates. We critically survey the size distributions and the related time-asymptotic scaling of droplet number and surface coverage. In the time-asymptotic regime, they admit a data collapse: the data for all substrates and condensation rates lie on universal scaling functions.Received 3 September 2020Accepted 24 January 2022DOI:https://doi.org/10.1103/PhysRevResearch.4.L012019Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasEmergence of patternsNucleationPhase transitionsPhysical SystemsDrops & bubblesNonequilibrium systemsPolydisperse materialsTechniquesFractal dimension characterizationPattern formationScaling methodsStatistical PhysicsPolymers & Soft Matter

Gruppo Prometeo's volunteering experience during the COVID-19 pandemic: an example of self-organization and heutagogy.

Gruppo Prometeo's volunteering experience during the COVID-19 pandemic: an example of self-organization and heutagogy.

Larval Zebrafish Exhibit Collective Circulation in Confined Spaces

Collective behavior may be elicited or can spontaneously emerge by a combination of interactions with the physical environment and conspecifics moving within that environment. To investigate the relative contributions of these factors in a small millimeter-scale swimming organism, we observed larval zebrafish, interacting at varying densities under circular confinement. If left undisturbed, larval zebrafish swim intermittently in a burst and coast manner and are socially independent at this developmental stage, before shoaling behavioral onset. Our aim was to explore the behavior these larvae as they swim together inside circular confinements. We report here our analysis of a new observation for this well-studied species: in circular confinement and at sufficiently high densities, the larvae collectively circle rapidly alongside the boundary. This is a new physical example of self-organization of mesoscale living active matter driven by boundaries and environment geometry. We believe this is a step forward toward using a prominent biological model system in a new interdisciplinary context to advance knowledge of the physics of social interactions.

Cyberspace as an Example of Self-Organisation from a Network Perspective

The present contribution defends network theory empirically by considering the governance of cyberspace. It aims to normatively explain the largely non-state regulation of cyberspace with the help of network theory. To this end, it first introduces key conglomerates of cyberspace governance and analyses their structures and processes. The empirical analysis of the organisational structures forms the basis for the concluding theoretical evaluation. The contribution can serve as an impulse for further research on global governance in a departure from state-centred perceptions.

Common principles of early mammalian embryo self-organisation.

Pre-implantation mammalian development unites extreme plasticity with a robust outcome: the formation of a blastocyst, an organised multi-layered structure ready for implantation. The process of blastocyst formation is one of the best-known examples of self-organisation. The first three cell lineages in mammalian development specify and arrange themselves during the morphogenic process based on cell-cell interactions. Despite decades of research, the unifying principles driving early mammalian development are still not fully defined. Here, we discuss the role of physical forces, and molecular and cellular mechanisms, in driving self-organisation and lineage formation that are shared between eutherian mammals.

Cellular self-organization: generating order from the abyss.

While the organization of inanimate systems such as gases or liquids is predominantly thermodynamically driven—a mixture of two gases will tend to mix until they reach equilibrium—biological systems frequently exhibit organization that is far from a well-mixed equilibrium. The anisotropies displayed by cells are evident in some of the dynamic processes that constitute life including cell development, movement, and division. These anisotropies operate at different length-scales, from the meso- to the nanoscale, and are proposed to reflect self-organization, a characteristic of living systems that is becoming accessible to reconstitution from purified components, and thus a more thorough understanding. Here, some examples of self-organization underlying cellular anisotropies at the cellular level are reviewed, with an emphasis on Rho-family GTPases operating at the plasma membrane. Given the technical challenges of studying these dynamic proteins, some of the successful approaches that are being employed to study their self-organization will also be considered.

Self-Organization When Pedestrians Move in Opposite Directions. Multi-Lane Circular Track Model

When pedestrians walk along a corridor in both directions, a frequently observed phenomenon is the segregation of the whole group into lanes of individuals moving in the same direction. While this formation of lanes facilitates the flow and benefits the whole group, it is believed that results from the actions of the individuals acting on their behalf, without considering others. This phenomenon is an example of self-organization and has attracted the attention of a number of researchers in diverse fields. We introduce and analyze a simple model. We assume that individuals move around a multi-lane circular track. All of them move at the same speed. Half of them in one direction and the rest in the opposite direction. Each time two individuals collide, one of them moves to a neighboring lane. The individual changing lanes is selected randomly. We prove that the system self-organizes. Eventually, each lane is occupied with individuals moving in only one direction. Our analysis supports the belief that global self-organization is possible even if each member of the group acts without considering the rest.

Percolation in a reduced equilibrium model of planar cell polarity.

Planar cell polarity (PCP) is a biological phenomenon where a large number of cells get polarized and coordinatedly align in a plane. PCP is an example of self-organization through local and global interactions between cells. In this work, we have used a lattice-based spin model for PCP that mimics the alignment of cells through local interactions. We have investigated the equilibrium behavior of this model. In this model, alignment of cells leads to the formation of clusters of aligned cells, and such clustering exhibits percolation transition. Even though the alignment of a cell in this model depends upon its neighbors, finite-size scaling analysis shows that this model belongs to the universality class of simple two-dimensional random percolation.

Numerical prediction of colloidal phase separation by direct computation of Navier\u2013Stokes equation

Numerical prediction of out-of-equilibrium processes in soft and bio matter containing liquids is highly desirable. However, it is quite challenging primarily because the motions of the components at different hierarchical levels (e.g., large colloids and small solvent molecules) are spatio-temporally coupled in a complicated manner via momentum conservation. Here we critically examine the predictability of numerical simulations for colloidal phase separation as a prototype example of self-organization of soft materials containing a liquid. We use coarse-grained hydrodynamic simulations to tackle this problem, and succeed in almost perfectly reproducing the structural and topological evolution experimentally observed by three-dimensional confocal microscopy without any adjustable parameters. Furthermore, comparison with non-hydrodynamic simulations shows the fundamental importance of many-body hydrodynamic interactions in colloidal phase separation. The predictive power of our computational approach may significantly contribute to not only the basic understanding of the dynamical behavior and self-organization of soft, bio and active matter but also the computer-aided design of colloidal materials.

Pattern Generation with Nucleic Acid Chemical Reaction Networks.

Biological and biochemical systems are manifestations of chemical reaction networks (CRNs). The ability to design and engineer such networks may allow the construction of artificial systems that are as complex as those seen in biology, opening the way to translational possibilities including adaptive materials. One venue for progress is the design of autonomous systems capable of pattern generation; however many synthetic CRNs, such as the Belousov-Zhabotinsky reaction, cannot be rewired to encode more complex interactions and thus lack the capacity for more detailed engineering algorithms. In contrast, DNA is an information-rich molecule with predictable and reliable base-pairing interactions and well-studied kinetics, and the use of DNA has greatly enabled the rational design of much more complex synthetic CRNs. Recent advances in the DNA computing field include circuits for pattern transformation, an example of self-organization. An arsenal of tools for designing DNA circuits to implement various CRNs has been developed by DNA nanotechnologists, including software to reliably program strand-displacement nucleic acid circuits. In addition, DNA walkers can be used to create CRNs with controlled diffusivity, while DNA gels similarly represent a new medium for implementing CRNs that may ultimately lead to the development of smart materials. As we will argue, future endeavors in nucleic acid-based pattern generation will be most greatly advanced by harnessing well-known enzymatic processes to serve as generators and amplifiers. Once nucleic acid computing tools are further developed to expedite the design process of pattern generation, we anticipate a transition from proof-of-concept curiosities to application-driven inquiries.

Enzyme functioning: Along the lines of nonequilibrium phase transitions

In recent decades the mechanisms of regulation of enzyme activity attract growing attention. Even the cornerstone schemes and notions of enzymology, such as the Michaelis-Menten scheme or cooperativity, undergo permanent refinements and revisions. Theoretical interpretations of new data, however, remain within the standard chemical kinetics framework. Although this admits qualitative explanations of some significant regulation phenomena like performance of ‘hysteretic’ enzymes, many characteristic features of enzymatic reactions (essentially nonexponential kinetics, dependence of rate constants on substrate concentration, and others) can hardly be accommodated. On the other hand, the inherent factors of enzyme functioning – flux conditions, slow structural changeability, nonlinear feedback between fast reaction acts and slow conformational rearrangements – provide a natural basis for self-organization phenomena. While their typical manifestations are related to macroscopic systems, the enzyme functioning can serve as an example of self-organization on the lowest possible level, down to single molecules. We put forward this concept of dynamical molecular self-organization in early 90’s and then developed its theoretical and experimental substantiations with the example of primary reactions of photosynthesis. In this work, I apply it to the Michaelis-Menten scheme. Within this paradigm, suitable for either ensemble or single molecule conditions, the stable functional regimes of enzyme operation emerge and interchange/coexist due to analogues of nonequilibrium phase transitions determined by the strength of substrate-conformation interaction and controlled by substrate concentration. In particular, the phenomena like ‘monomeric cooperativity’ or self-inhibition naturally follow from even the simplest two-state model of an enzyme with an only binding site.

Synchronization of chaotic systems: A microscopic description

The synchronization of coupled chaotic systems represents a fundamental example of self organization and collective behavior. This well-studied phenomenon is classically characterized in terms of macroscopic parameters, such as Lyapunov exponents, that help predict the systems transitions into globally organized states. However, the local, microscopic, description of this emergent process continues to elude us. Here we show that at the microscopic level, synchronization is captured through a gradual process of topological adjustment in phase space, in which the strange attractors of the two coupled systems continuously converge, taking similar form, until complete topological synchronization ensues. We observe the local nucleation of topological synchronization in specific regions of the systems attractor, providing early signals of synchrony, that appear significantly before the onset of complete synchronization. This local synchronization initiates at the regions of the attractor characterized by lower expansion rates, in which the chaotic trajectories are least sensitive to slight changes in initial conditions. Our findings offer an alternative description of synchronization in chaotic systems, exposing its local embryonic stages that are overlooked by the currently established global analysis. Such local topological synchronization enables the identification of configurations where prediction of the state of one system is possible from measurements on that of the other, even in the absence of global synchronization.

History and development of Haken's synergetics

History of the emergence, establishment and development of Haken's synergetics is thoroughly considered. Synergetics as a quite young view of the world has originated due to the necessity of finding adequate, reasonable, calculated and forecasted by science answers to global challenges that civilizational human development makes. Synergetics is a general theory of self-organization. It formulates the general principles of self-organization, which are true for all levels of matter. A peculiarity of synergetic approach is the transition from research of simple systems to the complex ones, from open to closed ones, from linear to nonlinear ones, from the study of equilibrium and process near the equilibrium to the delocalization and instability, to the investigation of things, which are happening far from equilibrium. The contribution of the science schools and H. Haken to the establishment of synergetics is revealed. This article mentions the perspectives of development of Haken's synergetics, nonlinear dynamics as the methodology of solution to the problems, which the economy and the whole society face. Nonlinear dynamics offers the basic models, new terms and methods, which can or cannot be used in such situation. They can become the framework for building the new nonlinear cognitive paradigm or they can stay the separate discoveries in different disciplines. Synergetics is formed as an interdisciplinary scientific approach, which develops the methods of investigation of open systems' behavior and the complex behavior of their components. The perspectives of the use of synergetics in science research are represented. Some systems in physics, chemistry and biology provide the simplest examples of self-organization. Modern areas of research within the framework of synergetics and nonlinear dynamics are considered. The results formed a strong basis for the further research in the field of economic science regarding synergetics. Synergetics is a powerful mathematical tool to analyze and solve modern nonlinear economic phenomena, which form the synergetic system and can't be described by classic economic-mathematical methods. Synergetics is one of effective approaches to general problems of the description of complexity, characteristic of phenomena of self-organization.

Topological three-dimensional dissipative optical solitons.

This article presents a review of recent investigations of topological three-dimensional (3D) dissipative optical solitons in homogeneous laser media with fast nonlinearity of amplification and absorption. The solitons are found numerically, with their formation, by embedding two-dimensional laser solitons or their complexes in 3D space after their rotation around a vortex straight line with their simultaneous twist. After a transient, the 'hula-hoop' solitons can form with a number of closed and unclosed infinite vortex lines, i.e. the solitons are tangles in topological notation. They are attractors and are characterized by extreme stability. The solitons presented here can be realized in lasers with fast saturable absorption and are promising for information applications. The tangle solitons of the type described present an example of self-organization that can be found not only in optics but also in various distributed dissipative systems of different types.This article is part of the theme issue 'Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 1)'.