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In this work we have studied the stripe domain structure created by single pulse IR laser irradiation in CLT crystals covered by a conductive layer. The formation of three types of domain patterns was distinguished: (1) the central region with curved stripe domains, (2) the middle region with straight rays and branches oriented in three directions, and (3) the wide edge region covered by parallel straight rays oriented in only one direction. The obtained results have been considered as domain growth in highly-nonequilibrium switching conditions under the action of spatially nonuniform pyroelectric field arising during cooling after pulse laser irradiation. [ABSTRACT FROM AUTHOR]

In this work, we have studied the shape evolution of the isolated domains in domain array in congruent lithium niobate crystals under the action of pyroelectric fields arising during multiple irradiation by laser pulses. The loss of the circle shape with the pulse number was obtained in the arrays of isolated domains arising at the edges of the irradiated zone. The simulation of the domain growth under the action of the pyroelectric field allowed revealing two stages of domain shape evolution in the regular domain array. An important role of the neighboring domains was revealed. [ABSTRACT FROM AUTHOR]

Biological membranes are complex, heterogeneous, and dynamic systems that play roles in the compartmentalization and protection of cells from the environment. It is still a challenge to elucidate kinetics and real-time transport routes for molecules through biological membranes in live cells. Currently, by developing and employing super-resolution microscopy; increasing evidence indicates channels and transporter nano-organization and dynamics within membranes play an important role in these regulatory mechanisms. Here we review recent advances and discuss the major advantages and disadvantages of using super-resolution microscopy to investigate protein organization and transport within plasma membranes.

G protein–coupled receptors are the largest and pharmacologically most important receptor family and are involved in the regulation of most cell functions. Most of them reside exclusively at the cell surface, from where they signal via heterotrimeric G proteins to control the production of second messengers such as cAMP and IP3 as well as the activity of several ion channels. However, they may also internalize upon agonist stimulation or constitutively reside in various intracellular locations. Recent evidence indicates that their function differs depending on their precise cellular localization. This is because the signals they produce, notably cAMP and Ca2+, are mostly bound to cell proteins that significantly reduce their mobility, allowing the generation of steep concentration gradients. As a result, signals generated by the receptors remain confined to nanometer-sized domains. We propose that such nanometer-sized domains represent the basic signaling units in a cell and a new type of target for drug development. [ABSTRACT FROM AUTHOR]

Driven by the increasing demands in advanced aerospace engineering, the integrated structural and functional materials are explored. In present study, we fabricate the TiB w /Ti–V–Al lightweight shape memory alloy composites with large recoverable strain (>5 %), high specific strength (>200 MPa cm3/g) and good elongation (>20 %). The satisfied structural and functional performances are attributed to the unique gradient microstructure, including TiB whiskers, short-range martensitic nanodomains and long-range martensitic microdomains. TiB w with the optimized orientation exhibits high load-bearing capacity. The transition area between TiB w and matrix is composed of short-range martensitic nanodomains. Nanodomains are affected by the diffused interstitial B atoms and local internal stress field regulated by TiB w. The elastic interaction energy between nanodomains and TiB w are calculated according to the Eshelby method. Upon deformation, nanodomains grow to long-range martensitic laths. The long-range martensitic laths keep stable after unloading. The microstructure evolution ties well with the Landau free energy model. It achieves effective loading transfer from matrix to reinforcement phase, resulting in less irreversible defects and better shape memory effect. In addition, grain refinement strengthening, loading transfer strengthening and solution strengthening are utilized to achieve the improvement of the strength and plasticity. The finding offers a promising inspiration for the development of new type shape memory alloy composites with integrated structural and functional properties. [ABSTRACT FROM AUTHOR]

Biological membranes are complex, heterogeneous, and dynamic systems that play roles in the compartmentalization and protection of cells from the environment. It is still a challenge to elucidate kinetics and real-time transport routes for molecules through biological membranes in live cells. Currently, by developing and employing super-resolution microscopy; increasing evidence indicates channels and transporter nano-organization and dynamics within membranes play an important role in these regulatory mechanisms. Here we review recent advances and discuss the major advantages and disadvantages of using super-resolution microscopy to investigate protein organization and transport within plasma membranes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zulueta Diaz and Arnspang.)

Ferroelectricity has recently been demonstrated in germanium-based halide perovskites. We use first-principles-based simulations to study 4-18 nm CsGeBr 3 films and develop a theory for ferroelectric ultrathin films. The theory introduces (i) a local order parameter, which identifies phase transitions into both monodomain and polydomain phases, and (ii) a dipole pattern classifier, which allows efficient and reliable identification of dipole patterns. Application of the theory to both halides CsGeBr 3 and CsGeI 3 and oxide BiFeO 3 ultrathin ferroelectrics reveals two distinct scenarios. First, the films transition into a monodomain phase below the critical value of the residual depolarizing field. Above this critical value, the second scenario occurs, and the film undergoes a transition into a nanodomain phase. The two scenarios exhibit opposite responses of Curie temperature to thickness reduction. Application of a dipole pattern classifier reveals rich nanodomain phases in halide films: nanostripes, labyrinths, zig-zags, pillars, and lego domains.

The soybean root system is complex. In addition to being composed of various cell types, the soybean root system includes the primary root, the lateral roots, and the nodule, an organ in which mutualistic symbiosis with N-fixing rhizobia occurs. A mature soybean root nodule is characterized by a central infection zone where atmospheric nitrogen is fixed and assimilated by the symbiont, resulting from the close cooperation between the plant cell and the bacteria. To date, the transcriptome of individual cells isolated from developing soybean nodules has been established, but the transcriptomic signatures of cells from the mature soybean nodule have not yet been characterized. Using single-nucleus RNA-seq and Molecular Cartography technologies, we precisely characterized the transcriptomic signature of soybean root and mature nodule cell types and revealed the co-existence of different sub-populations of B. diazoefficiens-infected cells in the mature soybean nodule, including those actively involved in nitrogen fixation and those engaged in senescence. Mining of the single-cell-resolution nodule transcriptome atlas and the associated gene co-expression network confirmed the role of known nodulation-related genes and identified new genes that control the nodulation process. For instance, we functionally characterized the role of GmFWL3, a plasma membrane microdomain-associated protein that controls rhizobial infection. Our study reveals the unique cellular complexity of the mature soybean nodule and helps redefine the concept of cell types when considering the infection zone of the soybean nodule., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

[Display omitted] • DiphenylPhosphate(DPP)/bis(2-ethylhexyl)Amine(BEEA) mixtures show optical birefringence if subjected to a magnetic field. • Magnetically-induced birefringence data suggests that DPP-BEEA anisotropy contrasts that shown by unassociated species. • Around DPP molar ratio 0.1–0.2, a probable percolation of DPP/BEEA ionic liquid domains takes place. Diphenyl phosphate (DPP)/bis(2-ethylhexyl) amine (BEEA) liquid mixtures are expected to show peculiar self-assembly behavior due to their, respectively, acidic and basic nature which can trigger acid-base reaction. The properties of DPP/BEEA mixtures of different compositions are explored by a combined theoretical (Ab initio calculations) and experimental (rheology, X-ray and light scattering) approach. (i) a proton transfer from DPP to BEEA takes place with formation of cationic and anionic species in liquid phase (ion pair formation); (ii) due to the strong and long-range electrostatic interactions, each of the two charged species is preferentially surrounded by the other one, in a picture resembling the structure of ionic materials; (iii) this gives rise to a striking viscosity increase takes place as DPP concentration increases; (iv) the composition dependencies of all measured parameters show clear deviations around DPP molar fraction of 0.2, indicating unequivocally the formation of isolated domains, formed by DPP-BEEA pairs which coalescence/percolate into a unique, extended, network at higher DPP concentrations. [ABSTRACT FROM AUTHOR]

• The superparaelectric phase engineering is employed in BNT RFE ceramics to realize high energy storage performance. • A novel approach has been introduced to assess the linear relaxation characteristics. • A remarkable W rec value of 7.2 J⋅cm−3 together with a high η of 86 % can be obtained. The utilization of electrostatic energy storage technology, which relies on dielectrics, is of utmost importance in the realm of advanced electronics and high-power electrical systems. However, there is still a lack of a universally applicable method to simultaneously attain elevated recoverable energy density (W rec) and high efficiency (η). Herein, based on the design of superparaelectric regulation, SmFeO 3 was introduced into the typical 0.6Bi 0.5 Na 0.5 TiO 3 –0.4Sr 0.7 Bi 0.2 TiO 3 relaxor. A nearly linear P – E loop with near-zero remanent polarization and excellent comprehensive performance were realized in the 0.9(0.6Bi 0.5 Na 0.5 TiO 3 –0.4Sr 0.7 Bi 0.2 TiO 3)–0.1SmFeO 3 ceramic. A remarkable W rec value of 7.2 J⋅cm−3 together with a high η of 86% was obtained at an improved Weibull breakdown electric field (E b) of 430 kV⋅cm−1. Wherein the ultra-small nanodomain size and the increased linearity of the P – E loop based on superparaelectric regulation strategy at largely enhanced E b are responsible for the improvement of W rec and η. Therefore, the method of superparaelectric regulation realized on relaxor ferroelectrics opens a new avenue for the progress of cutting-edge ceramic capacitors. [ABSTRACT FROM AUTHOR]

Specific membrane lipids play unique roles in (macro)autophagy. Those include phosphatidylethanolamine, to which LC3/GABARAP autophagy proteins become covalently bound in the process, or cardiolipin, an important effector in mitochondrial autophagy (or mitophagy). Ceramide (Cer), or N-acyl sphingosine, is one of the simplest sphingolipids, known as a stress signal in the apoptotic pathway. Moreover, Cer is increasingly being recognized as an autophagy activator, although its mechanism of action is unclear. In the present review, the proposed Cer roles in autophagy are summarized, together with some biophysical properties of Cer in membranes. Possible pathways for Cer activation of autophagy are discussed, including specific protein binding of the lipid, and Cer-dependent perturbation of bilayer properties. Cer generation of lateral inhomogeneities (domain formation) is given special attention. Recent biophysical results, including fluorescence and atomic force microscopy data, show Cer-promoted enhanced binding of LC3/GABARAP to lipid bilayers. These observations could be interpreted in terms of the putative formation of Cer-rich nanodomains. • Ceramide is increasingly being recognized as an autophagy activator. • Ceramide enhanced binding of LC3/GABARAP autophagy proteins to lipid bilayers. • The above could be related to formation of ceramide-rich nanodomains. • Ceramide perturbation of bilayer properties might also help in autophagy enhancement. [ABSTRACT FROM AUTHOR]

Strain glass transition attracts increasing attention in ferroelastic alloys in the context that martensitic transformation serves as the dominant mechanism for shape memory alloys. However, observing the coexistence of strain glass transition and martensitic transformation has not been reported. In this work, we introduce the strain glass transition by doping element to form highly nickel-rich Ni 55 Ti 45 at.% alloys and in the meantime attain the characteristics of martensitic transformation in the alloys. We confirm the existence of strain glass transition by 1) no exothermic/endothermic peaks in heat flow curves, 2) two deviations in electric resistivity curves, 3) two frequency-dependent dips of storage modulus, and 4) successive formation and constrained growth of nanodomains over a wide temperature range. We observe the martensitic transformation characterized by 1) two pronounced exothermic peaks upon cooling and one endothermic peak upon heating in heat flow curves, 2) thermal hysteresis in electric resistivity curves, and 3) macroscopic martensitic twins in transmission electron microscopy images. With these two phase transformations, the quasilinear superelasticity, high strength, and large elastocaloric Δ T ad of up to 9.7 K are achieved. By designing the strain maps and microstructural evolution pathways, we have provided a temperature-composition transformation path diagram to offer mechanistic insights and tuning strategies for the development of advanced alloys. [Display omitted] [ABSTRACT FROM AUTHOR]

Lead-free antiferroelectrics with excellent energy storage performance can become the core components of the next-generation advanced pulse power capacitors. However, the low energy storage efficiency caused by the hysteresis of antiferroelectric-ferroelectric transition largely limits their development toward miniaturization, lightweight, and integration. In this work, an ultrahigh recoverable energy storage density of ≈11.4 J cm -3 with a high efficiency of ≈80% can be realized in La-modified Ag 0.5 Na 0.5 NbO 3 antiferroelectric ceramics at an ultrahigh breakdown electric field of ≈67 kV mm -1 by the compromise optimization between antiferroelectricity enhancement and nanodomain engineering, resulting in the transformation of large-size ferrielectric antipolar stripe domains into ultrasmall antiferroelectric nanodomains or polarization nanoregions revealing as Moiré fringe structures. In addition, the enhanced transparency with increasing La content can also be clearly observed. This work not only develops new lead-free antiferroelectric energy storage materials with high application potential but also demonstrates that the strategy of compromise optimization between antiferroelectricity modulation and nanodomain engineering is an effective avenue to enhance the energy storage performance of antiferroelectrics., (© 2023 Wiley-VCH GmbH.)

We describe a method for investigating lateral membrane heterogeneity using cryogenic electron microscopy (cryo-EM) images of liposomes. The method takes advantage of differences in the thickness and molecular density of ordered and disordered phases that are resolvable in phase contrast cryo-EM. Compared to biophysical techniques like FRET or neutron scattering that yield ensemble-averaged information, cryo-EM provides direct visualization of individual vesicles and can therefore reveal variability that would otherwise be obscured by averaging. Moreover, because the contrast mechanism involves inherent properties of the lipid phases themselves, no extrinsic probes are required. We explain and discuss various complementary analyses of spatially resolved thickness and intensity measurements that enable an assessment of the membrane's phase state. The method opens a window to nanodomain structure in synthetic and biological membranes that should lead to an improved understanding of lipid raft phenomena., (Copyright © 2024. Published by Elsevier Inc.)