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In recent years, studies have shed light on the physiological role of plant glutamate receptor-like channels (GLRs). However, the mechanism by which these channels are activated, and in particular, what is the physiological role of their binding to amino acids, remains elusive. The first direct biochemical demonstration that the Arabidopsis thaliana GLR3.3 isoform binds glutamate and other amino acids in a low micromolar range of concentrations was reported only recently. The first crystal structures of the ligand-binding domains of AtGLR3.3 and AtGLR3.2 isoforms also have been released. We foresee that these new experimental pieces of evidence provide the basis for a better understanding of how GLRs are activated and modulated in different physiological responses.

We found that a high-strength elastomer was obtained by the heat elongation of a thermoplastic polyurethane (TPU) film consisting of a high content of crystalline hard segments (HS). The stress upturn continuously increased with the elongation ratio without a decrease in the strain recovery by heat elongation, i.e., the stress at break of a quenched TPU film was increased from 55 to 136 MPa by heat elongation at an elongation ratio of 300%. The results of small-angle X-ray scattering, DSC, and AFM observations revealed that: (1) anisotropically shaped HS domains were stacked at a nanometer scale and the longer direction of the HS domains was arranged perpendicular to the elongated direction due to the heat elongation, (2) the densification of the HS domains increased with increases in the elongation ratio without a significant increase in the crystallinity, and (3) the stacked domain structure remained during the stretching at 23 °C. Thus, the strengthening of the elongated TPU might be attributed to the densification of the HS domains in the stacked structure, which prevents the fracture of the HS domains during the stretching.

— The magnetic-domain structure of the surface of microwires with the composition Fe 73.9 B 13.2 Si 10.9 C 2 is studied by magnetic-force microscopy. It is found that removal of the glass shell by chipping leads to distortion of the original magnetic-domain structure. Chemical etching of the glass shell makes it possible to observe the magnetic-domain structure due to the stresses that arise as a result of microwire production. In the absence of an applied magnetic field, a magnetic-domain structure of the surface layer consisting of domain layers inclined to the microwire axis by 45 or 135 degrees is observed. This structure has a close-to-zigzag-like shape. The thickness of the domain layers is not constant and varies from 3 to 5 μm. The application of a constant magnetic field along the microwire axis is found to cause the formation of ring domain layers of various thicknesses (from 1 to 5 μm) with different orientations of the magnetic moment relative to the microwire surface. In a field of 60 Oe along the microwire axis, the magnetic-domain structure consists of only ring layers of domains. Magnetic-field inversion leads to almost complete inversion of the observed domain structure. In this case, complete removal of the magnetic field leads to the formation of a new domain structure of the surface layer. Such a structure is close in shape and position of the domains to the original one, but does not repeat it.

A wide variety of two- and three-dimensional physical-chemical systems display domain patterns in equilibrium. The phenomenology of these patterns, and of the shapes of their constituent domains, is reviewed here from a point of view that interprets these patterns as a manifestation of modulated phases. These phases are stabilized by competing interactions and are characterized by periodic spatial variations of the pertinent order parameter, the corresponding modulation period generally displaying a dependence on temperature and other external fields. This simple picture provides a unifying framework to account for striking and substantial similarities revealed in the prevalent \"stripe\" and \"bubble\" morphologies as well as in commonly observed, characteristic domain-shape instabilities. Several areas of particular current interest are discussed.

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric.

Results from studying the effect of an applied electric voltage on the Raman spectrum of graphene deposited on a lithium niobate crystal substrate with a ferroelectric domain structure are presented. The use of the principal component method for data processing in combination with correlation analysis made it possible to reveal the contribution to the change in the spectra associated with the linear deformation of the substrate due to the inverse piezoelectric effect. An effect of the graphene coating peeling was found. Furthermore, bending deformations of the graphene coating associated with the presence of a relief on the substrate were found. An analysis of the change in the spectra of graphene under the application of an electric voltage made it possible to determine the height of this relief.

The basic magnetic properties of three-dimensional nanostructured materials can be drastically different from those of a continuous film. High-resolution magnetic force microscopy studies of magnetic submicrometer-sized cobalt dots with geometrical dimensions comparable to the width of magnetic domains reveal a variety of intricate domain patterns controlled by the details of the dot geometry. By changing the thickness of the dots, the width of the geometrically constrained magnetic domains can be tuned. Concentric rings and spirals with vortex configurations have been stabilized, with particular incidence in the magnetization reversal process as observed in the ensemble-averaged hysteresis loops.

Glutamate‐gated ion channels (ionotropic glutamate receptors, iGluRs) sense the extracellular milieu via an extensive extracellular portion, comprised of two clamshell‐shaped segments. The distal, N‐terminal domain (NTD) has allosteric potential in NMDA‐type iGluRs, which has not been ascribed to the analogous domain in AMPA receptors (AMPARs). In this study, we present new structural data uncovering dynamic properties of the GluA2 and GluA3 AMPAR NTDs. GluA3 features a zipped‐open dimer interface with unconstrained lower clamshell lobes, reminiscent of metabotropic GluRs (mGluRs). The resulting labile interface supports interprotomer rotations, which can be transmitted to downstream receptor segments. Normal mode analysis reveals two dominant mechanisms of AMPAR NTD motion: intraprotomer clamshell motions and interprotomer counter‐rotations, as well as accessible interconversion between AMPAR and mGluR conformations. In addition, we detect electron density for a potential ligand in the GluA2 interlobe cleft, which may trigger lobe motions. Together, these data support a dynamic role for the AMPAR NTDs, which widens the allosteric landscape of the receptor and could provide a novel target for ligand development. The crystal structure of the AMPA receptor subunit GluA3 N‐terminal domain (NTD) reveals unexpected structural flexibility of the NTD that might affect ion channel activity.

Transparent piezoelectrics are highly desirable for numerous hybrid ultrasound–optical devices ranging from photoacoustic imaging transducers to transparent actuators for haptic applications 1 – 7 . However, it is challenging to achieve high piezoelectricity and perfect transparency simultaneously because most high-performance piezoelectrics are ferroelectrics that contain high-density light-scattering domain walls. Here, through a combination of phase-field simulations and experiments, we demonstrate a relatively simple method of using an alternating-current electric field to engineer the domain structures of originally opaque rhombohedral Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT) crystals to simultaneously generate near-perfect transparency, an ultrahigh piezoelectric coefficient d 33 (greater than 2,100 picocoulombs per newton), an excellent electromechanical coupling factor k 33 (about 94 per cent) and a large electro-optical coefficient γ 33 (approximately 220 picometres per volt), which is far beyond the performance of the commonly used transparent ferroelectric crystal LiNbO 3 . We find that increasing the domain size leads to a higher d 33 value for the [001]-oriented rhombohedral PMN-PT crystals, challenging the conventional wisdom that decreasing the domain size always results in higher piezoelectricity 8 – 10 . This work presents a paradigm for achieving high transparency and piezoelectricity by ferroelectric domain engineering, and we expect the transparent ferroelectric crystals reported here to provide a route to a wide range of hybrid device applications, such as medical imaging, self-energy-harvesting touch screens and invisible robotic devices. The use of alternating-current electric fields to control domain size in ferroelectric crystals affords excellent transparency, piezoelectricity and birefringence.

Ferrotoroidicity goes fourth The defining property of ferroic materials — that's the ferromagnets, ferroelectrics and ferroelastics — is that of forming domains, based on magnetization, electric polarization and elastic strain respectively. It makes these materials of great technological importance, for instance in data storage as ferroelectric memory or as ferromagnetic domains written on a hard disk. But a fourth form of ferroic order has been postulated, based on an ordered arrangement of magnetic vortices or 'toroidization'. One of the prerequisites for this fourth form — called ferrotoroidicity — has now been observed , in the form of domains of opposite ferrotoroidic orientation. The ferrotoroidic domains were observed optically on lithium cobal phosphate (LiCoPO4), coexisting with independent antiferromagnetic domains. The ferrotoroidic state differs from the other forms of ferroic order in its asymmetric behaviour under the reversal of time and space. This asymmetry could lead to exciting possibilities for future applications. There are currently three types of ferroic materials that are widely known; ferromagnets, ferroelectricity, and ferroelastic materials. A fourth form of ferroic order, ferrotoroidicity, has been postulated. To confirm that a material is a ferrotorodic, corresponding ferrotoroidic domains need to be observed. Spatially resolved measurements with a nonlinear optical imaging method on LiCoPO 4 were carried out, and observed ferrotoroidic domains that coexist with independent antiferromagnetic domains. Domains are of unparalleled technological importance as they are used for information storage and for electronic, magnetic and optical switches. They are an essential property of any ferroic material. Three forms of ferroic order are widely known: ferromagnetism, a spontaneous magnetization; ferroelectricity, a spontaneous polarization; and ferroelasticity, a spontaneous strain. It is currently debated whether to include an ordered arrangement of magnetic vortices as a fourth form of ferroic order, termed ferrotoroidicity. Although there are reasons to expect this form of order from the point of view of thermodynamics 1 , a crucial hallmark of the ferroic state—that is, ferrotoroidic domains—has not hitherto been observed. Here ferrotoroidic domains are spatially resolved by optical second harmonic generation in LiCoPO 4 , where they coexist with independent antiferromagnetic domains. Their space- and time-asymmetric nature relates ferrotoroidics to multiferroics with magnetoelectric phase control 2 , 3 , 4 , 5 and to other systems in which space and time asymmetry leads to possibilities for future applications.