The bee
            Tetragonula
            builds its comb like a crystal

Stingless bees of the genus Tetragonula construct a brood comb with a spiral or a target pattern architecture in three dimensions. Crystals possess these same patterns on the molecular scale. Here, we show that the same excitable-medium dynamics governs both crystal nucleation and growth and comb construction in Tetragonula , so that a minimal coupled-map lattice model based on crystal growth explains how these bees produce the structures seen in their bee combs.

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Peculiarities of Protein Crystal Nucleation and Growth

Crystals ◽

10.3390/cryst8110422 ◽

2018 ◽

Vol 8 (11) ◽

pp. 422 ◽

Cited By ~ 8

Author(s):

Christo Nanev

Keyword(s):

Crystallization Process ◽

Protein Crystallization ◽

Nucleation And Growth ◽

Crystal Nucleation ◽

Protein Crystal ◽

Solution Flow ◽

Molecular Scale ◽

Novel Approaches ◽

Lattice Formation ◽

Complete Account

This paper reviews investigations on protein crystallization. It aims to present a comprehensive rather than complete account of recent studies and efforts to elucidate the most intimate mechanisms of protein crystal nucleation. It is emphasized that both physical and biochemical factors are at play during this process. Recently-discovered molecular scale pathways for protein crystal nucleation are considered first. The bond selection during protein crystal lattice formation, which is a typical biochemically-conditioned peculiarity of the crystallization process, is revisited. Novel approaches allow us to quantitatively describe some protein crystallization cases. Additional light is shed on the protein crystal nucleation in pores and crevices by employing the so-called EBDE method (equilibration between crystal bond and destructive energies). Also, protein crystal nucleation in solution flow is considered.

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The Nature and Crystal Growth of Otoconia in the Rat

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348947508400105 ◽

1975 ◽

Vol 84 (1) ◽

pp. 22-36 ◽

Cited By ~ 45

Author(s):

Muriel D. Ross ◽

Donald R. Peacor

Keyword(s):

Crystal Growth ◽

Structural Unit ◽

Integrated Approach ◽

Nucleation And Growth ◽

Organic Substrate ◽

Crystal Nucleation ◽

Chemical Factor ◽

Adult Type ◽

Inorganic Crystal ◽

Parallel Growth

Several types of otoconia are present in the macular regions of young rats. These include multifaceted, transitional and rounded body forms, some variant otoconia and a few rhombohedrons. The adult form has typically rounded but nonsmooth body surfaces and pointed ends with three planar faces. The multifaceted and transitional otoconia fracture and etch more readily than do the adult type. The differences in properties of the otoconia are considered in the light of known facts concerning inorganic crystal nucleation and growth. This integrated approach indicates that many otoconia originate by seeding of multiple subunits on an organic substrate and develop by the mechanism of parallel growth. The basic structural unit is the rhombohedron. By analogy to inorganic crystals of calcite, it would seem that the typical otoconium grows on the end faces but growth on the side faces is suppressed by some unknown chemical factor. Some otoconia are exceptions, evidently seeding and growing in the pure rhombohedral form. Decalcification of cleaved otoconia shows that organic material is incorporated during growth. The observations are interpreted to indicate that organic substance influences growth and achievement of the adult otoconial form.

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A double cell for controlling nucleation and growth of protein crystals

Journal of Applied Crystallography ◽

10.1107/s0021889888012270 ◽

1989 ◽

Vol 22 (2) ◽

pp. 115-118 ◽

Cited By ~ 13

Author(s):

M. Przybylska

Keyword(s):

Crystal Growth ◽

Protein Crystallization ◽

Heavy Atom ◽

Nucleation And Growth ◽

The Other ◽

Crystal Nucleation ◽

Diffusion Method ◽

Vapour Diffusion ◽

Reservoir Solution ◽

The Stability

A simple device for protein crystallization is described that consists of two connected cells, one for the hanging- or sitting-drop vapour diffusion method and the other for changing the concentration of the reservoir solution. It has been found useful for decoupling crystal nucleation from crystal growth, for improving the size and the stability of crystals, and in the preparation of heavy-atom derivatives.

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Coupled-map lattice model for crystal growth

Physical Review A ◽

10.1103/physreva.42.6125 ◽

1990 ◽

Vol 42 (10) ◽

pp. 6125-6128 ◽

Cited By ~ 20

Author(s):

David A. Kessler ◽

Herbert Levine ◽

W. N. Reynolds

Keyword(s):

Crystal Growth ◽

Lattice Model ◽

Coupled Map Lattice

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High-sensitivity image encryption algorithm with random cross diffusion based on dynamically random coupled map lattice model

Chaos Solitons & Fractals ◽

10.1016/j.chaos.2020.110582 ◽

2021 ◽

Vol 143 ◽

pp. 110582

Author(s):

Xingyuan Wang ◽

Jingjing Yang ◽

Nana Guan

Keyword(s):

Image Encryption ◽

Lattice Model ◽

High Sensitivity ◽

Coupled Map Lattice ◽

Encryption Algorithm ◽

Cross Diffusion ◽

Image Encryption Algorithm

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Molecular Dynamics Simulations of Crystal Nucleation near Interfaces in Incompatible Polymer Blends

Polymers ◽

10.3390/polym13030347 ◽

2021 ◽

Vol 13 (3) ◽

pp. 347

Author(s):

Wenlin Zhang ◽

Lingyi Zou

Keyword(s):

Molecular Dynamics ◽

Polymer Blends ◽

Md Simulations ◽

Nucleation And Growth ◽

Crystal Nucleation ◽

Crystalline Order ◽

Mobile Species ◽

Deep Supercooling ◽

Crystallizable Polymer ◽

Dynamics Simulations

We apply molecular dynamics (MD) simulations to investigate crystal nucleation in incompatible polymer blends under deep supercooling conditions. Simulations of isothermal nucleation are performed for phase-separated blends with different degrees of incompatibility. In weakly segregated blends, slow and incompatible chains in crystallizable polymer domains can significantly hinder the crystal nucleation and growth. When a crystallizable polymer is blended with a more mobile species in interfacial regions, enhanced molecular mobility leads to the fast growth of crystalline order. However, the incubation time remains the same as that in pure samples. By inducing anisotropic alignment near the interfaces of strongly segregated blends, phase separation also promotes crystalline order to grow near interfaces between different polymer domains.

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Phase separation in undercooled molten Pd80Si20: Part I

Journal of Materials Research ◽

10.1557/jmr.1999.0493 ◽

1999 ◽

Vol 14 (9) ◽

pp. 3653-3662 ◽

Cited By ~ 31

Author(s):

K. L. Lee ◽

H. W. Kui

Keyword(s):

Growth Rate ◽

Phase Separation ◽

Crystal Growth ◽

Grain Refinement ◽

Crystallization Temperature ◽

Sharp Decrease ◽

Nucleation And Growth ◽

Crystal Growth Rate ◽

Large Undercooling ◽

Kinetic Crystallization

Three different kinds of morphology are found in undercooled Pd80Si20, and they dominate at different undercooling regimens ΔT, defined as ΔT = T1 – Tk, where T1 is the liquidus of Pd80Si20 and Tk is the kinetic crystallization temperature. In the small undercooling regimen, i.e., for ΔT ≤ 190 K, the microstructures are typically dendritic precipitation with a eutecticlike background. In the intermediate undercooling regimen, i.e., for 190 ≤ ΔT ≤ 220 K, spherical morphologies, which arise from nucleation and growth, are identified. In addition, Pd particles are found throughout an entire undercooled specimen. In the large undercooling regimen, i.e., for ΔT ≥ 220 K, a connected structure composed of two subnetworks is found. A sharp decrease in the dimension of the microstructures occurs from the intermediate to the large undercooling regimen. Although the crystalline phases in the intermediate and the large undercooling regimens are the same, the crystal growth rate is too slow to bring about the occurrence of grain refinement. Combining the morphologies observed in the three undercooling regimens and their crystallization behaviors, we conclude that phase separation takes place in undercooled molten Pd80Si20.

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