Formation and role of colloid material structures and surfaces in chemical reaction system: Part II

In a thermodynamically open, non-isotherm, non-continuous, multicomponent, initially homogeneously distributed chemical reaction system far from equilibrium, quasi-stationary states and a heterogeneous spatial structure divided by surface boundaries may emerge spontaneously by self-organisation. This structure emerges, evolves and devolves over time as chemical reactions are completed. During this process, reactants segregate themselves in space, the rate of the mass transport and the chemical process partly decreases, both processes become periodic, new types of material exchange mechanisms unusual in inanimate nature arise, and feedback and self-regulation occur which promote the survival of the structure produced. Roles of boundary surfaces and solubility in generation of new type periodic or cyclic phenomena were discussed.     

A simple access to ω-aminoalkyltrialkoxysilanes: Tunable linkers for self-organised organosilicas

A simple route to ω-aminoalkyltriethoxysilanes with variable alkylene chain lengths, (EtO)₃Si(CH₂)_nNH₂ (n = 5, 11) is described. These silyl linkers have been used to prepare urea-based compounds with H-bonding and hydrophobic interactions which enable the self-assembly of the molecules. These molecular precursors are suitable for the obtention of nano-structured hybrid silicas.     

Studies on interpolymer self-organisation behaviour of protoporphyrin IX bound poly(carboxylic acid)s with complimentary polymers by means of fluorescence techniques

Covalently bound protoporphyrin IX was used as a fluorophore to investigate the interpolymer complex formation between the poly(carboxylic acid)s, PMAA/PAA and poly(N-vinyl pyrrolidone), PVP, poly(ethylene oxide), PEO or poly(ethylene glycol), PEG. Absorption and emission spectral properties of protoporphyrin IX bound to PAA, PMAA and PVP have been studied. Protoporphyrin IX in poly(MAA-co-PPIX) was found to be present in the dimer or higher aggregated form at low pH due to the environmental restriction imposed by the polymer whereas in the case of poly(AA-co-PPIX) and poly(VP-co-PPIX), PPIX exists in monomeric form. The fluorescence intensity and lifetime of PPIX bound to poly(carboxylic acid)s increase on complexation through hydrogen bonding with PVP, PEO and PEG due to the displacement of water molecules in the vicinity of the PPIX. Poly(MAA-co-PPIX) shows longer fluorescence lifetime due to the more compact interpolymer complexation as compared to poly(AA-co-PPIX) due to the enhanced hydrophobicity of PMAA. Poly(VP-co-PPIX) shows a decrease in the fluorescence lifetime on complexation with PMAA or PAA due to the hydrophilic and microgel like environment of the fluorophore bound to PVP. The contrasting behaviour of the same polymer adduct with respect to the site of the fluorophore is interpreted to be due to the solvent structure which determines the environment of the fluorophore.     

Highly-ordered SiGe-islands grown by dislocation patterning using ion-assisted MBE

Fabrication of device structures based on laterally self-ordered systems without the use of expensive and time-consuming nanolithography could have undoubted advantages. For such applications, it is proposed to use misfit dislocation networks from partially relaxed SiGe layers on (1 0 0) Si substrate as a template for the growth of highly ordered SiGe islands. Ion bombardment during molecular beam epitaxy of metastable SiGe layers leads to such a partial relaxation by misfit dislocation networks. The ions are generated by the interaction of the evaporated Si flux with the electrons in an electron beam evaporator, which causes a partial ionization of Si atoms in the molecular beam. We demonstrate by atomic force microscopy that subsequent growth of SiGe on such relaxed SiGe (25-50% Ge) layers leads to the formation of uniform three-dimensional islands highly ordered in 〈1 1 0〉 directions.     

Cognition coming about: Self-organisation and free-energy: Commentary on Wright,J.J. and Bourke,P.D. (2020) “The growth of cognition: Free energy minimization and the embryogenesis of cortical computation”

Wright and Bourke's compelling article rightly points out that existing models of embryogenesis fail to explain the mechanisms and functional significance of the dynamic connections among neurons. We pursue their account of Dynamic Logic by appealing to the Markov blanket formalism that underwrites the Free Energy Principle. We submit that this allows one to model embryogenesis as self-organisation in a dynamical system that minimises free-energy. The ensuing formalism may be extended to also explain the autonomous emergence of cognition, specifically in the brain, as a dynamic self-assembling process.     

Metabolic Systemic Computing: Exploiting Innate Immunity within an Artificial Organism for On-line Self-Organisation and Anomaly Detection

Previous work suggests that innate immunity and representations of tissue can be useful when combined with artificial immune systems. Here we provide a new implementation of tissue for artificial immune systems using systemic computation, a new model of computation and corresponding computer architecture based on a systemics world-view and supplemented by the incorporation of natural characteristics. We show using systemic computation how to create an artificial organism, a program with metabolism that eats data, expels waste, self-organise cells based on the nature of its food and emits danger signals suitable for an artificial immune system. The implementation is tested by application to two standard machine learning sets and shows excellent abilities to recognise anomalies in its diet as well as a consistent datawise self-organisation.     

Monte Carlo simulation of age-dependent host-parasite relations

The death of a biological population is an extreme event which we investigate here for a host-parasitoid system. Our simulations using the Penna ageing model show how biological evolution can “teach” the parasitoids to avoid extinction by waiting for the right age of the host. We also show the dependence of extinction time on the population size.     

Formation and role of colloid material structures and surfaces in chemical reaction system: Part I

In the methyl-chloroformate/methanol/water reaction system with initially homogeneous distribution a stationary heterogeneous spatial structure divided by surface boundaries may emerge spontaneously through self-organisation.

This structure emerges, evolves and devolves over time as chemical reactions are completed. After the completion of the chemical reactions, the reaction media are homogeneously distributed again.     

Layered self-organized structures on poly(3-octylthiophene) thin films studied by scanning probe microscopy

The morphology and mechanical properties of poly-(3-octylthiophene) P3OT films thin has been studied by scanning force microscopy techniques. On these films we find self-assembled layered structures that appear regardless of the preparation conditions, that is, spin-coating or drop-casting, of the solvent concentration or of the type of substrate. Using the drop-casting method for sample preparation these layered structures are hardly visible due to the high surface roughness, while using spin-coating these structures are the main topographic feature on the surface. These structures have typically one or two layers, even though occasionally up to four layers have been observed. Each layer has a height of 4-5 nm, which is associated to crystalline P3OT domains and lay on the polymer film. The size of these structures increases with increasing concentration of the P3OT in the solvent. We find well differentiated morphological, electrostatic as well as mechanical properties for the self-assembled structures as compared to the rest of the polymer film. Finally, the growth rate of these structures has been studied.