scholarly journals Classification and Evolutionary Trends of Icosahedral Viral Capsids

2008 ◽  
Vol 9 (3-4) ◽  
pp. 175-181 ◽  
Author(s):  
Richard Kerner
Keyword(s):  
Building Blocks ◽  
The Self ◽  
Self Organization ◽  
Evolutionary Trends ◽  
Viral Capsids ◽  
Exact Number ◽  
Evolution Of Viruses ◽  
Simple Rules ◽  
Elementary Building

A classification of icosahedral viral capsids is proposed. We show how the self-organization of capsids during their formation implies a definite composition of their elementary building blocks. The exact number of hexamers with three different admissible symmetries is related to capsids' sizes, labelled by theirT-numbers. Simple rules determining these numbers for each value ofTare deduced and certain consequences concerning the probabilities of mutations and evolution of viruses are discussed.

scholarly journals An artificial spiking quantum neuron

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lasse Bjørn Kristensen ◽  
Matthias Degroote ◽  
Peter Wittek ◽  
Alán Aspuru-Guzik ◽  
Nikolaj T. Zinner
Keyword(s):  
Time Series Prediction ◽  
Dynamical Evolution ◽  
Building Blocks ◽  
Quantum Correlations ◽  
Neuromorphic Hardware ◽  
Local Measurements ◽  
Non Local ◽  
Elementary Building ◽  
Learning Protocols

AbstractArtificial spiking neural networks have found applications in areas where the temporal nature of activation offers an advantage, such as time series prediction and signal processing. To improve their efficiency, spiking architectures often run on custom-designed neuromorphic hardware, but, despite their attractive properties, these implementations have been limited to digital systems. We describe an artificial quantum spiking neuron that relies on the dynamical evolution of two easy to implement Hamiltonians and subsequent local measurements. The architecture allows exploiting complex amplitudes and back-action from measurements to influence the input. This approach to learning protocols is advantageous in the case where the input and output of the system are both quantum states. We demonstrate this through the classification of Bell pairs which can be seen as a certification protocol. Stacking the introduced elementary building blocks into larger networks combines the spatiotemporal features of a spiking neural network with the non-local quantum correlations across the graph.

scholarly journals Self-organization at air-water interfaces emerging from Marangoni and elastocapillary effects directed by amphiphile filament connections.

2021 ◽  
Author(s):  
Mitch Winkens ◽  
Peter A. Korevaar
Keyword(s):  
Driving Forces ◽  
Building Blocks ◽  
The Self ◽  
Self Organization ◽  
Marangoni Flow ◽  
Water Interface ◽  
Air Water Interface ◽  
Novel Method ◽  
Floating Objects ◽  
Self Organizing

Marangoni and elastocapillary effects are well-known as driving forces in the self-organization of floating objects at air-water interfaces. The release of surface active compounds generates Marangoni flows that cause repulsion, whereas capillary forces drive attraction. Typically, these interactions are non-directional and mechanisms to establish directional connections between the self-organizing elements are lacking. In this work, we unravel the mechanisms involved in the self-organization of a linear amphiphile into millimeter-long filaments that form connections between floating droplets. First, we show how the release of the amphiphile tetra(ethylene glycol) monododecyl ether from a floating source droplet onto the air-water interface generates a Marangoni flow. This flow extrudes self-assembled amphiphile filaments which grow from the source droplet, and concomitantly repels floating droplets in the surroundings. A hydrophobic drain droplet that depletes the amphiphiles from the air-water interface directs the Marangoni flow and thereby the growing filaments. We show how these filaments, upon tethering to the drain, potentially facilitate internal Marangoni convection and elastocapillary effects, which attract the drain back towards the source droplet. Furthermore, this concept establishes connections that are selective to the composition of the drain droplets – which influences the rate at which they deplete the amphiphile – such that repulsive and attractive forces can be balanced. Thereby, we provide a novel method through which directional attraction can be established in synthetic self-organizing systems, and advance our understanding of how complexity arises from simple building blocks.

scholarly journals Protein interface redesign facilitates the transformation of nanocage building blocks to 1D and 2D nanomaterials

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xiaorong Zhang ◽  
Yu Liu ◽  
Bowen Zheng ◽  
Jiachen Zang ◽  
Chenyan Lv ◽  
...  
Keyword(s):  
Self Assembly ◽  
Thermotoga Maritima ◽  
Building Blocks ◽  
The Self ◽  
Protein Interface ◽  
Protein Assemblies ◽  
Viral Capsids ◽  
2D Nanomaterials ◽  
External Stimuli ◽  
Artificial Protein

AbstractAlthough various artificial protein nanoarchitectures have been constructed, controlling the transformation between different protein assemblies has largely been unexplored. Here, we describe an approach to realize the self-assembly transformation of dimeric building blocks by adjusting their geometric arrangement. Thermotoga maritima ferritin (TmFtn) naturally occurs as a dimer; twelve of these dimers interact with each other in a head-to-side manner to generate 24-meric hollow protein nanocage in the presence of Ca2+ or PEG. By tuning two contiguous dimeric proteins to interact in a fully or partially side-by-side fashion through protein interface redesign, we can render the self-assembly transformation of such dimeric building blocks from the protein nanocage to filament, nanorod and nanoribbon in response to multiple external stimuli. We show similar dimeric protein building blocks can generate three kinds of protein materials in a manner that highly resembles natural pentamer building blocks from viral capsids that form different protein assemblies.

scholarly journals Frustrated self-assembly of non-Euclidean crystals of nanoparticles

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Francesco Serafin ◽  
Jun Lu ◽  
Nicholas Kotov ◽  
Kai Sun ◽  
Xiaoming Mao
Keyword(s):  
Self Assembly ◽  
Three Dimensional ◽  
Building Blocks ◽  
The Self ◽  
High Yield ◽  
Complex Structures ◽  
Interparticle Interactions ◽  
Viral Capsids ◽  
Self Organized ◽  
New Material

AbstractSelf-organized complex structures in nature, e.g., viral capsids, hierarchical biopolymers, and bacterial flagella, offer efficiency, adaptability, robustness, and multi-functionality. Can we program the self-assembly of three-dimensional (3D) complex structures using simple building blocks, and reach similar or higher level of sophistication in engineered materials? Here we present an analytic theory for the self-assembly of polyhedral nanoparticles (NPs) based on their crystal structures in non-Euclidean space. We show that the unavoidable geometrical frustration of these particle shapes, combined with competing attractive and repulsive interparticle interactions, lead to controllable self-assembly of structures of complex order. Applying this theory to tetrahedral NPs, we find high-yield and enantiopure self-assembly of helicoidal ribbons, exhibiting qualitative agreement with experimental observations. We expect that this theory will offer a general framework for the self-assembly of simple polyhedral building blocks into rich complex morphologies with new material capabilities such as tunable optical activity, essential for multiple emerging technologies.

scholarly journals A Stochastic Model of Icosahedral Capsid Growth

2005 ◽  
Vol 6 (2) ◽  
pp. 95-97 ◽  
Author(s):  
R. Kerner
Keyword(s):  
Stochastic Model ◽  
Building Blocks ◽  
Self Organization ◽  
High Yield ◽  
High Level ◽  
Elementary Building ◽  
Icosahedral Capsid

A model of growth of icosahedral capsids is proposed. It is similar to the stochastic model of fullerene growth, but takes into account variations in the composition of pentamers and hexamers that are responsible for the final capsid size. We show that the observed high yield of capsid production implies a high level of self-organization of the elementary building blocks.

scholarly journals Discrete Groups and Internal Symmetries of Icosahedral Viral Capsids

2014 ◽  
Vol 2 (1) ◽  
Author(s):  
Richard Kerner
Keyword(s):  
Self Organization ◽  
Symmetry Groups ◽  
Discrete Groups ◽  
Viral Capsids ◽  
Symmetry Classes ◽  
Special Cases ◽  
Internal Symmetries

Abstract A classification of all possible icosahedral viral capsids is proposed. It takes into account the diversity of hexamers’ compositions, leading to definite capsid size.We showhowthe self-organization of observed capsids during their production results from definite symmetries of constituting hexamers. The division of all icosahedral capsids into four symmetry classes is given. New subclasses implementing the action of symmetry groups Z2, Z3 and S3 are found and described. They concern special cases of highly symmetric capsids whose T = p2 + pq + q2-number is of particular type corresponding to the cases (p, 0) or (p, p).

Hierarchical design of nanostructured materials based on polyoxometalates

2009 ◽  
Vol 81 (12) ◽  
pp. 2369-2376 ◽  
Author(s):  
Noritaka Mizuno ◽  
Sayaka Uchida ◽  
Kazuhiro Uehara
Keyword(s):  
Nanostructured Materials ◽  
Building Blocks ◽  
The Self ◽  
Self Organization ◽  
Materials Chemistry ◽  
Hierarchical Design ◽  
Crystalline Materials ◽  
Molecular Building Blocks ◽  
Organization Process ◽  
Key Topics

The construction of nanostructured materials with advanced functions by the self-organization of molecular building blocks is one of the key topics in modern materials chemistry. This review describes our concept of the hierarchical design of polyoxometalate (POM)-based compounds with nanosized spaces: (1) syntheses of building blocks (POMs and counter cations), (2) directing the self-organization of building blocks to form crystalline materials with nanosized spaces, and (3) kinetic control of the self-organization process to introduce nanosized space into the dense nonporous crystal, with emphasis on (2). Our recent results on the construction of nanosized spaces within the POM-based compounds with controlled size, volume, shape, and affinity, and their functions are presented.

Self-Organization of Nanoscopic Building Blocks into Ordered Assemblies

2004 ◽  
Vol 818 ◽  
Author(s):  
Mark A. Horsch ◽  
Christopher R. Iacovella ◽  
Zhenli Zhang ◽  
Sharon C. Glotzer
Keyword(s):  
Computer Simulation ◽  
Liquid Crystals ◽  
Block Copolymers ◽  
Self Assembly ◽  
Building Blocks ◽  
The Self ◽  
Self Organization

AbstractWe studied the self-assembly of nanoscopic building blocks comprised of polymer-tethered nanoparticles using computer simulation and predict that these building blocks can assemble into mono- and multi-layer sheets and shells. The simulations further demonstrate that for some nanoparticle geometries and tethered nanoparticle topologies, ideas from block copolymers, surfactants and liquid crystals can be used to predict the ordered morphologies attained via self- assembly and that for specific cases the morphologies are consistent with Israelachvili packing rules.

Estimates of Ten Multiple Intelligences

2002 ◽  
Vol 7 (4) ◽  
pp. 245-255 ◽  
Author(s):  
Adrian Furnham ◽  
Thomas Li-Ping Tang ◽  
David Lester ◽  
Rory O'Connor ◽  
Robert Montgomery
Keyword(s):  
Multiple Intelligences ◽  
Male Partner ◽  
Bill Clinton ◽  
The Self ◽  
Tony Blair ◽  
Female Partners ◽  
American Students ◽  
Bill Gates ◽  
Nationality Differences

A total of 253 British and 318 American students were asked to make various estimates of overall intelligence as well as Gardner's (1999a) new list of 10 multiple intelligences. They made these estimations (11 in all) for themselves, their partner, and for various well-known figures such as Prince Charles, Tony Blair, Bill Gates, and Bill Clinton. Following previous research there were various sex and nationality differences in self-estimated IQ: Males rated themselves higher on verbal, logical, spatial, and spiritual IQ compared to females. Females rated their male partner as having lower verbal and spiritual, but higher spatial IQ than was the case when males rated their female partners. Participants considered Bill Clinton (2 points) and Prince Charles (5 points) less intelligent than themselves, but Tony Blair (5 points) and Bill Gates (15 points) more intelligent than themselves. Multiple regressions indicated that the best predictors of one's overall IQ estimates were logical, verbal, existential, and spatial IQ. Factor analysis of the 10 and then 8 self-estimated scores did not confirm Gardner's classification of multiple intelligences. Results are discussed in terms of the growing literature in the self-estimates of intelligence, as well as limitations of that approach.

Sign in / Sign up

Export Citation Format

Share Document