Publications by authors named "A I Kovalev"

Several plant seeds release a mucilaginous envelope through hydration, rich in pectins and stabilized by cellulose fibers. This mucilage aids in seed protection, development, and adhesion for dispersal. This study aimed to separate the effects of pectins and cellulose fibers by using pectinase to remove mucilage pectins, leaving cellulose arrays, and performing wet and dry pull-off force measurements on seeds of three plant species: Salvia hispanica (Chia), Collomia grandiflora (Collomia) and Linum usitatissimum (Flax).

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Water striders inhabit the elastic surface tension film of water, sharing their environment with other aquatic organisms. Their survival relies heavily on swift maneuverability and navigation around floating obstacles, which aids in the exploration of their habitat and in escaping from potential threats. Their high agility is strongly based on the ability to execute precise turns, enabling effective directional control.

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The distribution of Eucnemidae (Coleoptera: Elateroidea) of Iran is summarized and an annotated checklist of the Iranian Eucnemidae is provided. A total of 16 species within 13 genera in four subfamilies of the family are listed.

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Topologically protected magnetic skyrmions in magnetic materials are stabilized by an interfacial or bulk Dzyaloshinskii-Moriya interaction (DMI). Interfacial DMI decays with an increase of the magnetic layer thickness in just a few nanometers, and bulk DMI typically stabilizes magnetic skyrmions at low temperatures. Consequently, more flexibility in the manipulation of DMI is required for utilizing nanoscale skyrmions in energy-efficient memory and logic devices at room temperature (RT).

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We analyze a delay differential equation model for a frequency-swept semiconductor laser and demonstrate existence of extreme events in its dynamics, with probabilities heavily dependent on the sweep rate. The extreme events appear even in absence of any noise in the system and do not exhibit significant dependence on its presence. We investigate the problem numerically and show that intensity dynamics of these events are highly localized in the filter detuning space.

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