11 research outputs found
Spontaneous synchronization of two bistable pyridine-furan nanosprings connected by an oligomeric bridge
The intensive development of nanodevices acting as two-state systems has
motivated the search for nanoscale molecular structures whose long-term
conformational dynamics are similar to the dynamics of bistable mechanical
systems such as Euler arches and Duffing oscillators. Collective synchrony in
bistable dynamics of molecular-sized systems has attracted immense attention as
a potential pathway to amplify the output signals of molecular nanodevices.
Recently, pyridin-furan oligomers of helical shape that are a few nanometers in
size and exhibit bistable dynamics similar to a Duffing oscillator have been
identified through molecular dynamics simulations. In this article, we present
the case of dynamical synchronization of these bistable systems. We show that
two pyridine-furan springs connected by a rigid oligomeric bridge spontaneously
synchronize vibrations and stochastic resonance enhances the synchronization
effect
Spontaneous Vibrations and Stochastic Resonance of Short Oligomeric Springs
There is growing interest in molecular structures that exhibit dynamics
similar to bistable mechanical systems. These structures have the potential to
be used as nanodevices with two distinct states. Particularly intriguing are
structures that display spontaneous vibrations and stochastic resonance.
Previously, through molecular dynamics simulations, it was discovered that
short pyridine-furan springs, when subjected to force loading, exhibit the
bistable dynamics of a Duffing oscillator. In this study, we extend these
simulations to include short pyridine-pyrrole and pyridine-furan springs in a
hydrophobic solvent. Our findings demonstrate that these systems also display
the bistable dynamics of a Duffing oscillator, accompanied by spontaneous
vibrations and stochastic resonance activated by thermal noise.Comment: arXiv admin note: substantial text overlap with arXiv:2110.0409
Short Pyridine-Furan Springs Exhibit Bistable Dynamics of Duffing Oscillators
The intensive development of nanodevices acting as two-state systems has motivated the search for nanoscale molecular structures whose dynamics are similar to those of bistable mechanical systems, such as Euler arches and Duffing oscillators. Of particular interest are the molecular structures capable of spontaneous vibrations and stochastic resonance. Recently, oligomeric molecules that were a few nanometers in size and exhibited the bistable dynamics of an Euler arch were identified through molecular dynamics simulations of short fragments of thermo-responsive polymers subject to force loading. In this article, we present molecular dynamics simulations of short pyridine-furan springs a few nanometers in size and demonstrate the bistable dynamics of a Duffing oscillator with thermally-activated spontaneous vibrations and stochastic resonance
Short Pyridine-Furan Springs Exhibit Bistable Dynamics of Duffing Oscillators
The intensive development of nanodevices acting as two-state systems has motivated the search for nanoscale molecular structures whose dynamics are similar to those of bistable mechanical systems, such as Euler arches and Duffing oscillators. Of particular interest are the molecular structures capable of spontaneous vibrations and stochastic resonance. Recently, oligomeric molecules that were a few nanometers in size and exhibited the bistable dynamics of an Euler arch were identified through molecular dynamics simulations of short fragments of thermo-responsive polymers subject to force loading. In this article, we present molecular dynamics simulations of short pyridine-furan springs a few nanometers in size and demonstrate the bistable dynamics of a Duffing oscillator with thermally-activated spontaneous vibrations and stochastic resonance
Anisotropic Microgels by Supramolecular Assembly and Precipitation Polymerization of PyrazoleâModified Monomers
Abstract Soft colloidal macromolecular structures with programmable chemical functionalities, size, and shape are important building blocks for the fabrication of catalyst systems and adaptive biomaterials for tissue engineering. However, the development of the easy upscalable and templateâfree synthesis methods to obtain such colloids lack in understanding of molecular interactions that occur in the formation mechanisms of polymer colloids. Herein, a computer simulationâdriven experimental synthesis approach based on the supramolecular selfâassembly followed by polymerization of tailored pyrazoleâmodified monomers is developed. Simulations for a series of pyrazoleâmodified monomers with different numbers of pyrazole groups, different length and polarity of spacers between pyrazole groups and the polymerizable group are first performed. Based on simulations, monomers able to undergo ÏâÏ stacking and guide the formation of supramolecular bonds between polymer segments are synthesized and these are used in precipitation polymerization to synthesize anisotropic microgels. This study demonstrates that microgel morphologies can be tuned from spherical, raspberryâlike to dumbbellâlike by the increase of the pyrazoleâmodified monomer loading, which is concentrated at periphery of growing microgels. Combining experimental and simulation results, this work provides a quantitative and predictive approach for guiding microgel design that can be further extended to a diversity of colloidal systems and soft materials with superior properties
An Artificial PhaseâTransitional Underwater Bioglue with Robust and Switchable Adhesion Performance
Ionic Combisomes: A New Class of Biomimetic Vesicles to Fuse with Life
The construction of biomembranes that faithfully capture the properties and dynamic functions of cell membranes remains a challenge in the development of synthetic cells and their application. Here a new concept for synthetic cell membranes based on the selfâassembly of amphiphilic comb polymers into vesicles, termed ionic combisomes (iâcombisomes) is introduced. These combs consist of a polyzwitterionic backbone to which hydrophobic tails are linked by electrostatic interactions. Using a range of microscopies and molecular simulations, the selfâassembly of a library of combs in water is screened. It is discovered that the hydrophobic tails form the membrane's core and force the backbone into a rod conformation with nematicâlike ordering confined to the interface with water. This particular organization resulted in membranes that combine the stability of classic polymersomes with the biomimetic thickness, flexibility, and lateral mobility of liposomes. Such unparalleled matching of biophysical properties and the ability to locally reconfigure the molecular topology of its constituents enable the harboring of functional components of natural membranes and fusion with living bacteria to âhijackâ their periphery. This provides an almost inexhaustible palette to design the chemical and biological makeup of the iâcombisomes membrane resulting in a powerful platform for fundamental studies and technological applications
Ultra-strong bio-glue from genetically engineered polypeptides
The development of biomedical glues is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, i.e. strong adhesion and adaption to remodeling processes in healing tissue. Here, we report a biocompatible and biodegradable protein-based adhesive with high adhesion strengths. The maximum strength reaches 16.5 ± 2.2 MPa on hard substrates, which is comparable to that of commercial cyanoacrylate superglue and higher than other protein-based adhesives by at least one order of magnitude. Moreover, the strong adhesion on soft tissues qualifies the adhesive as biomedical glue outperforming some commercial products. Robust mechanical properties are realized without covalent bond formation during the adhesion process. A complex consisting of cationic supercharged polypeptides and anionic aromatic surfactants with lysine to surfactant molar ratio of 1:0.9 is driven by multiple supramolecular interactions enabling such strong adhesion. We demonstrate the glueâs robust performance in vitro and in vivo for cosmetic and hemostasis applications and accelerated wound healing by comparison to surgical wound closures
Biodiversity revision of a large arctic region as a basis for its monitoring and protection under conditions of active economic development (Nenetsky Autonomous Okrug, Russia)
In the scope of implementing a UNDP / GEF / Ministry of Nature project, a database and a GIS to consider the biodiversity of the Nenetsky Autonomous Okrug were developed. They include information on 2035 animal and 1640 plant species, belonging to 15 model groups. Data were obtained using publications and unpublished sources, the results of studying collections / herbaria of four institutes of the Russian Academy of Sciences, and data of fieldwork (2015) conducted in three coastal areas of Bolshezemelskaya Tundra. The taxonomic richness of the Nenetsky Autonomous Okrug biota is not lower (even higher in some animal groups) than in other large Arctic regions (e.g. Taymyr and Greenland). Some new vegetation syntaxa have been described. And some phytogeographic boundaries have been established. Several animal taxa have been described for the first time for science. Some of species were neither previously recorded in the Nenetsky Autonomous Okrug nor formerly known from Europe («Siberian» species), nor from Russia. Concerning types of ranges, the proportion of species having predominantly Siberian / East Palaearctic / Siberian-Nearctic ranges varied in different model groups from 0% to 30%. The fraction of arctic (in a wide sense) species ranged from 0% to 29%. We considered the status of the natural environment of the Nenetsky Autonomous Okrug to be satisfactory so far as its destruction is particularly local. We strongly confirm the need to create new Protected Areas. The material obtained during the project processing has been applied to the organisation of sanctuaries in the Khaipudyrskaya Bay and Pakhancheskaya Bay, Barents Sea