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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]

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]

Recently, the localization of amyloid precursor protein (APP) into reversible nanoscale supramolecular assembly or “nanodomains” has been highlighted as crucial towards understanding the onset of the molecular pathology of Alzheimer’s disease (AD). Surface expression of APP is regulated by proteins interacting with it, controlling its retention and lateral trafficking on the synaptic membrane. Here, we evaluated the involvement of a key risk factor for AD, PICALM, as a critical regulator of nanoscale dynamics of APP. Although it was enriched in the postsynaptic density, PICALM was also localized to the presynaptic active zone and the endocytic zone. PICALM colocalized with APP and formed nanodomains with distinct morphological properties in different subsynaptic regions. Next, we evaluated if this localization to subsynaptic compartments was regulated by the C-terminal sequences of APP, namely, the “Y682ENPTY687” domain. Towards this, we found that deletion of C-terminal regions of APP with partial or complete deletion of Y682ENPTY687, namely, APP–Δ9 and APP–Δ14, affected the lateral diffusion and nanoscale segregation of APP. Lateral diffusion of APP mutant APP–Δ14 sequence mimicked that of a detrimental Swedish mutant of APP, namely, APP–SWE, while APP–Δ9 diffused similar to wild-type APP. Interestingly, elevated expression of PICALM differentially altered the lateral diffusion of the APP C-terminal deletion mutants. These observations confirm that the C-terminal sequence of APP regulates its lateral diffusion and the formation of reversible nanoscale domains. Thus, when combined with autosomal dominant mutations, it generates distinct molecular patterns leading to onset of Alzheimer’s disease (AD). [ABSTRACT FROM AUTHOR]

The impact of microstructure on hardness in phase‐separated calcium aluminosilicate glasses is investigated. Changes in hardness are governed by microstructure deformations that occur during indentation. Phase separation leads to decreased hardness due to the incongruent yielding of the droplet and matrix phases. Moreover, the deformation of microstructures possessing dilute, spherical droplets did not have a significant impact on hardness. Microstructures characterized by concentrated, acicular droplets were found to deform through a process of droplet coalescence. This process absorbs additional energy during yielding and results in glasses that deform through droplet coalescence possessing improved hardness. [ABSTRACT FROM AUTHOR]

This paper deals with the problems encountered in the study of eukaryotic cell membranes. A discussion on the structure and composition of membranes, lateral heterogeneity of membranes, lipid raft formation, and involvement of actin and cytoskeleton networks in the maintenance of membrane structure is included. Modern methods for the study of membranes and their constituent domains are discussed. Various simplified models of biomembranes and lipid rafts are presented. Computer modelling is considered as one of the most important methods. This is stated that from the study of the plasma membrane structure, it is desirable to proceed to the diverse membranes of all organelles of the cell. The qualitative composition and molar content of individual classes of polar lipids, free sterols and proteins in each of these membranes must be considered. A program to create an open access electronic database including results obtained from the membrane modelling of individual cell organelles and the key sites of the membranes, as well as models of individual molecules composing the membranes, has been proposed. [ABSTRACT FROM AUTHOR]

Summary: In Arabidopsis, the receptor‐like kinase (RLK) FERONIA (FER) senses peptide ligands in the plasma membrane (PM), modulates plant growth and development, and integrates biotic and abiotic stress signaling for downstream adaptive responses. However, the molecular interplay of these diverse processes is largely unknown.Here, we show that FER, the receptor of Rapid Alkalinization Factor 1 (RALF1), physically interacts with C2 domain ABA‐related (CAR) proteins to control the nano‐organization of the PM. During this process, the RALF1‐FER pathway upregulates CAR protein translation, and then more CAR proteins are recruited to the PM. This acts as a rapid feedforward loop that stabilizes the PM liquid‐ordered phase. FER interacts with and phosphorylates CARs, thereby reducing their lipid‐binding ability and breaking the feedback regulation at later time points.The formation of the flg22‐induced FLS2‐BAK1 immune complex, which depends on the integrity of FER‐containing nanodomains, is impaired in fer and pentuple car14569 mutant.Together, we propose that the FER‐CAR module controls the formation of PM nano‐organization during RALF signaling through a self‐contained amplifying loop including both positive and negative feedback. [ABSTRACT FROM AUTHOR]

Cardiolipin (CL) is a key lipid for damaged mitochondrial recognition by the LC3/GABARAP human autophagy proteins. The role of ceramide (Cer) in this process is unclear, but CL and Cer have been proposed to coexist in mitochondria under certain conditions. Varela et al. showed that in model membranes composed of egg sphingomyelin (eSM), dioleoyl phosphatidylethanolamine (DOPE), and CL, the addition of Cer enhanced the binding of LC3/GABARAP proteins to bilayers. Cer gave rise to lateral phase separation of Cer-rich rigid domains but protein binding took place mainly in the fluid continuous phase. In the present study, a biophysical analysis of bilayers composed of eSM, DOPE, CL, and/or Cer was attempted to understand the relevance of this lipid coexistence. Bilayers were studied by differential scanning calorimetry, confocal fluorescence microscopy, and atomic force microscopy. Upon the addition of CL and Cer, one continuous phase and two segregated ones were formed. In bilayers with egg phosphatidylcholine instead of eSM, in which the binding of LC3/GABARAP proteins hardly increased with Cer in the former study, a single segregated phase was formed. Assuming that phase separation at the nanoscale is ruled by the same principles acting at the micrometer scale, it is proposed that Cer-enriched rigid nanodomains, stabilized by eSM:Cer interactions formed within the DOPE- and CL-enriched fluid phase, result in structural defects at the rigid/fluid nanointerfaces, thus hypothetically facilitatingLC3/GABARAP protein interaction. [ABSTRACT FROM AUTHOR]

Phosphatidylinositol‐3‐kinases (PI3Ks) are lipid kinases that produce 3‐phosphorylated derivatives of phosphatidylinositol upon activation by various cues. These 3‐phosphorylated lipids bind to various protein effectors to control many cellular functions. Lipid phosphatases such as phosphatase and tensin homolog (PTEN) terminate PI3K‐derived signals and are critical to ensure appropriate signaling outcomes. Many lines of evidence indicate that PI3Ks and PTEN, as well as some specific lipid effectors are highly compartmentalized, either in plasma membrane nanodomains or in endosomal compartments. We examine the evidence for specific recruitment of PI3Ks, PTEN, and other related enzymes to membrane nanodomains and endocytic compartments. We then examine the hypothesis that scaffolding of the sources (PI3Ks), terminators (PTEN), and effectors of these lipid signals with a common plasma membrane nanodomain may achieve highly localized lipid signaling and ensure selective activation of specific effectors. This highlights the importance of spatial regulation of PI3K signaling in various physiological and disease contexts. [ABSTRACT FROM AUTHOR]

Biological milieus are highly crowded and heterogeneous systems where organization of macromolecules within nanodomains (e.g. membraneless compartments) is vital to the regulation of metabolic processes. There is an increasing interest in understanding the effects that such packed environments have on different biochemical and biological processes. In this context, the redox biochemistry and redox signaling fields are moving towards investigating oxidative processes under conditions that exhibit these key features of biological systems in order to solve existing paradigms including those related to the generation and transmission of specific redox signals within and between cells in both normal physiology and under conditions of oxidative stress. This review outlines the effects that crowding, nanodomain formation and altered local viscosities can have on biochemical processes involving proteins, and then discusses some of the reactions and pathways involving proteins and oxidants that may, or are known to, be modulated by these factors. We postulate that knowledge of protein modification processes (e.g. kinetics, pathways and product formation) under conditions that mimic biological milieus, will provide a better understanding of the response of cells to endogenous and exogenous stressors, and their role in ageing, signaling, health and disease. [Display omitted] • Biological systems are heavily crowded and heterogeneous environments. • These factors may influence protein oxidation, glycation and redox signaling. • Crowding modulates reaction kinetics, and the extent and sites of modification. • Crowding enhances chain reactions, and alters product yields and cross-linking. • Nanodomains and membraneless organelles can facilitate redox signaling. [ABSTRACT FROM AUTHOR]

Dielectric ceramics are fundamental for electronic systems, including energy storages, microwave applications, ultrasonics, and sensors. Relaxor ferroelectrics show superb performance among dielectrics due to their high efficiency and energy density by the nature of nanodomains. Here, a novel non‐perovskite relaxor ferroelectric, Bi6Ti5WO22, with ultralow loss, ≈10−3, highly tunable permittivity, ≈2200 at room temperature with 40% tunability and the superparaelectric region at room temperature is presented. The actual crystal structure and the nanodomains of Bi6Ti5WO22 are demonstrat Various‐temperature neutron powder diffraction and in situ high‐resolution transmission‐electron‐microscopy illustrate the twinning effect, subtle structure change and micro‐strain in the material influenced by temperature, manifesting the actual crystal structure of Bi6Ti5WO22. Compared with dielectric loss of BaTiO3‐based dielectric tunable materials, the loss of Bi6Ti5WO22 is more than an order of magnitude lower, which makes it exhibit a figure of merit (≈240), much higher than that of conventional dielectric tunable materials (< 100), endorse the material great potential for direct applications. The present research offers a strategy for discovering novel relaxor ferroelectrics and a highly desirable material for fabricating energy storage capacitors, microwave dielectrics, and ultrasonics. [ABSTRACT FROM AUTHOR]

Dielectric ceramics are fundamental for electronic systems, including energy storages, microwave applications, ultrasonics, and sensors. Relaxor ferroelectrics show superb performance among dielectrics due to their high efficiency and energy density by the nature of nanodomains. Here, a novel non‐perovskite relaxor ferroelectric, Bi6Ti5WO22, with ultralow loss, ≈10−3, highly tunable permittivity, ≈2200 at room temperature with 40% tunability and the superparaelectric region at room temperature is presented. The actual crystal structure and the nanodomains of Bi6Ti5WO22 are demonstrat Various‐temperature neutron powder diffraction and in situ high‐resolution transmission‐electron‐microscopy illustrate the twinning effect, subtle structure change and micro‐strain in the material influenced by temperature, manifesting the actual crystal structure of Bi6Ti5WO22. Compared with dielectric loss of BaTiO3‐based dielectric tunable materials, the loss of Bi6Ti5WO22 is more than an order of magnitude lower, which makes it exhibit a figure of merit (≈240), much higher than that of conventional dielectric tunable materials (< 100), endorse the material great potential for direct applications. The present research offers a strategy for discovering novel relaxor ferroelectrics and a highly desirable material for fabricating energy storage capacitors, microwave dielectrics, and ultrasonics. [ABSTRACT FROM AUTHOR]

Bi4−xNdxFeTi2O12 (BNFTO, x = 0, 0.5, 1.0, and 1.5) Aurivillius three‐layered ceramics are prepared via a solid‐state reaction method. The crystal structure of the compounds reveals that the compounds exhibit a major orthorhombic structure with the B2cb space group. Slight distortions in the orthorhombic unit cell and an increase in cell volume with the doping of Nd are observed. Highly dense randomly oriented plate‐like nonuniform grains are observed in the micrographs of the ceramics. A decrease in energy bandgap values is noticed in Nd‐doped ceramics from 2.88 to 2.18 eV. An increase in polarization values is observed with Nd doping due to the improved grain boundaries. The appearance of a weak ferromagnetic nature at low temperature followed by a decline in magnetic interaction at room temperature (RT) is observed for all compounds. The frequency and temperature variations of the dielectric constant are investigated. The frequency and temperature variations of the impedance measurements indicate that compounds exhibit non‐Debye‐type electrical relaxations and a negative temperature coefficient of resistance. Furthermore, single‐peak relaxations are predominant for all measured samples, mainly the contribution of intragranular grain regions. This makes Nd‐dopant BNFTO Aurivillius ceramics have a great research value for RT multiferroic applications. [ABSTRACT FROM AUTHOR]

Accumulation of aggregates of the microtubule‐binding protein Tau is a pathological hallmark of Alzheimer's disease. While Tau is thought to primarily associate with microtubules, it also interacts with and localizes to the plasma membrane. However, little is known about how Tau behaves and organizes at the plasma membrane of live cells. Using quantitative, single‐molecule imaging, we show that Tau exhibits spatial and kinetic heterogeneity near the plasma membrane of live cells, resulting in the formation of nanometer‐sized hot spots. The hot spots lasted tens of seconds, much longer than the short dwell time (∼ 40 ms) of Tau on microtubules. Pharmacological and biochemical disruption of Tau/microtubule interactions did not prevent hot spot formation, suggesting that these are different from the reported Tau condensation on microtubules. Although cholesterol removal has been shown to reduce Tau pathology, its acute depletion did not affect Tau hot spot dynamics. Our study identifies an intrinsic dynamic property of Tau near the plasma membrane that may facilitate the formation of assembly sites for Tau to assume its physiological and pathological functions. Synopsis: The cytosolic leaflet of the plasma membrane has long been suggested as a site for Tau to execute some of its functions. However, how this protein behaves and organizes at the plasma membrane of live cells remains largely unknown. Using single‐molecule super‐resolution imaging, this study quantifies Tau's spatiotemporal organization at a nanoscale level in this compartment. Tau exists in multiple spatial and kinetic subpopulations near the plasma membrane.Preventing Tau/microtubule interactions biochemically or pharmacologically increases the mobility of individual Tau molecules.Tau forms dynamic, nanometer‐sized hot spots lasting tens of seconds.Tau's mobility is reduced within the hot spots.Tau hot spots persist even after the disruption of Tau/microtubule interactions and cholesterol depletion. [ABSTRACT FROM AUTHOR]

We review the current theories of nanodomain, or "raft," formation. We emphasize that the idea that they are co-exisiting Lo and Ld phases is fraught with difficulties, as is the closely related idea that they are due to critical fluctuations. We then review an alternate theory that the plasma membrane is a two-dimensional microemulsion, and that the mechanism that drives to zero the line tension between Lo and Ld phases is the coupling of height and composition fluctuations. The theory yields rafts of SM and cholesterol in the outer leaf and POPS and POPC in the inner leaf. The "sea" between rafts consists of POPC in the outer leaf and POPE and cholesterol in the inner leaf. The characteristic size of the domain structures is tens of nanometers. [ABSTRACT FROM AUTHOR]

Summary: Phosphatidylinositol 4‐phosphate (PI4P) is an anionic phospholipid which has been described as a master regulator of the Golgi apparatus in eukaryotic cells. However, recent evidence suggests that PI4P mainly accumulates at the plasma membrane in all plant cells analyzed so far. In addition, many functions that are typically attributed to phosphatidylinositol 4,5‐bisphosphate (PI(4,5)P2) in animal and yeast cells are also supported by PI4P in plants. For example, PI4P is the key anionic lipid that powers the strong electrostatic properties of the plasma membrane. Phosphatidylinositol 4‐phosphate is also required for the establishment of stable membrane contacts between the endoplasmic reticulum and the plasma membrane, for exocytosis and to support signaling pathways. Thus, we propose that PI4P has a prominent role in specifying the identity of the plasma membrane and in supporting some of its key functions and should be considered a hallmark lipid of this compartment. [ABSTRACT FROM AUTHOR]

Strain glass is a new strain state discovered recently in ferroelastic systems that is characterized by nanoscale martensitic domains formed through a freezing transition. These nanodomains typically have mottled or tweed morphology depending on the elastic anisotropy of the system. Strain glass transition is a broadly smeared and high order–like transition, taking place within a wide temperature or stress range. It is accompanied by many unique properties, including linear superelasticity with high strength, low modulus, Invar and Elinvar anomalies, and large magnetostriction. In this review, we first discuss experimental characterization and testing that have led to the discovery of the strain glass transition and its unique properties. We then introduce theoretical models and computer simulations that have shed light on the origin and mechanisms underlying the unique characteristics and properties of strain glass transitions. Unresolved issues and challenges in strain glass study are also addressed. Strain glass transition can offer giant elastic strain and ultralow elastic modulus by well-controlled reversible structural phase transformations through defect engineering. [ABSTRACT FROM AUTHOR]

Despite its low abundance, phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is a key modulator of membrane-associated signaling events in eukaryotic cells. Temporal and spatial regulation of PI(4,5)P2 concentration can achieve localized increases in the levels of this lipid, which are crucial for the activation or recruitment of peripheral proteins to the plasma membrane. The recent observation of the dramatic impact of physiological divalent cation concentrations on PI(4,5)P2 clustering, suggests that protein anchoring to the plasma membrane through PI(4,5)P2 is likely not defined solely by a simple (monomeric PI(4,5)P2)/(protein bound PI(4,5)P2) equilibrium, but instead depends on complex protein interactions with PI(4,5)P2 clusters. The insertion of PI(4,5)P2-binding proteins within these clusters can putatively modulate protein–protein interactions in the membrane, but the relevance of such effects is largely unknown. In this work, we characterized the impact of Ca2+ on the organization and protein–protein interactions of PI(4,5)P2-binding proteins. We show that, in giant unilamellar vesicles presenting PI(4,5)P2, the membrane diffusion properties of pleckstrin homology (PH) domains tagged with a yellow fluorescent protein (YFP) are affected by the presence of Ca2+, suggesting direct interactions between the protein and PI(4,5)P2 clusters. Importantly, PH-YFP is found to dimerize in the membrane in the absence of Ca2+. This oligomerization is inhibited in the presence of physiological concentrations of the divalent cation. These results confirm that cation-dependent PI(4,5)P2 clustering promotes interactions between PI(4,5)P2-binding proteins and has the potential to dramatically influence the organization and downstream interactions of PI(4,5)P2-binding proteins in the plasma membrane. [ABSTRACT FROM AUTHOR]

Lead-free piezoelectric actuators emerge as promising substitutes for their lead-containing counterparts to address environmental concerns. However, they often confront a trade-off between low driving electric fields and high electro-strain. Herein, a novel strategy to boost electro-strain under low electric fields is proposed by doping high-electronegativity B-site atoms into perovskite potassium sodium niobate-based ceramics. Our findings reveal that high-electronegativity B-site atoms elevate the covalency of B-O bonding, softening the short-range repulsion and introducing local multiphase coexistence. This leads to more nanoscale domain structures and lower coercive field, thereby enabling large strains to be produced at lower electric fields. Notably, a substantial 0.2 % bipolar electro-strain and 0.1 % unipolar electro-strain under 10 kV cm-1 is achieved in Sr, Sb co-doped potassium sodium niobate ceramics, with a broad working frequency and temperature range, as well as excellent fatigue resistance. This study unveils innovative insights into designing lead-free piezoelectric ceramics with remarkable electro-strain performance and low driving electric field, promising a significant advancement in lead-free piezoelectric materials science and piezoelectric actuators. [Display omitted] [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]

Extracellular vesicles (EVs) are secreted from all cell types and are intimately involved in tissue homeostasis. They are being explored as vaccine and gene therapy platforms, as well as potential biomarkers. As their size is below the diffraction limit of light microscopy, direct visualizations have been daunting and single‐particle studies under physiological conditions have been hampered. Here, direct stochastic optical reconstruction microscopy (dSTORM) was employed to visualize EVs in three‐dimensions and to localize molecule clusters such as the tetraspanins CD81 and CD9 on the surface of individual EVs. These studies demonstrate the existence of membrane microdomains on EVs. These were confirmed by Cryo‐EM. Individual particle visualization provided insights into the heterogeneity, structure, and complexity of EVs not previously appreciated [ABSTRACT FROM AUTHOR]

Glasses with nanoscale phase separation have the potential to possess improved hardness and fracture toughness while maintaining their optical transparency. Here we present the results of isothermal heat treatments of phase‐separated calcium aluminosilicate glasses. Our results indicate that a transition from Lifshitz–Slozof–Wagner (LSW)‐type kinetics to a diffusion‐controlled pseudo‐coalescence mechanism occurs at ~17% droplet volume fraction, which results in the droplets becoming increasingly elongated and interconnected. The activation barrier for both mechanisms suggests that calcium diffusion is the underlying means for the coarsening of the silica‐rich domains. Simple approximations show the transition cannot be explained by Brownian motion or Van der Waals attraction between domains, and instead suggest various osmotic forces may be responsible. [ABSTRACT FROM AUTHOR]

α2δ proteins (CACNA2D1–4) are required for normal neurological function and contribute to membrane trafficking of voltage‐gated calcium channels, through which calcium entry initiates numerous physiological processes. However, it remains unclear how α2δ proteins influence calcium‐mediated signalling to control neuronal output. Using whole‐cell recordings of mouse Purkinje cells, we show that α2δ‐2 is required for functional coupling of postsynaptic voltage‐dependent calcium entry with calcium‐dependent effector mechanisms controlling two different outputs, depolarization‐induced suppression of excitation and spike afterhyperpolarization. Our findings indicate an important role for α2δ‐2 proteins in regulating functional postsynaptic calcium channel coupling in neurons, providing new context for understanding the effects of α2δ mutations on neuronal circuit function and presenting additional potential avenues to manipulate α2δ‐mediated signalling for therapeutic gain. Key points: Calcium influx, via voltage‐dependent calcium channels, drives numerous neuronal signalling processes with precision achieved in part by tight coupling between calcium entry and calcium‐dependent effectors.α2δ proteins are important for neurological function and contribute to calcium channel membrane trafficking, although how α2δ proteins influence postsynaptic calcium‐dependent signalling is largely unexplored.Here it is shown that loss of α2δ‐2 proteins disrupts functional calcium coupling to two different postsynaptic calcium‐dependent signals in mouse Purkinje cell neurons, retrograde endocannabinoid signalling and the action potential afterhyperpolarization.The findings provide new insights into the control of calcium coupling as well as new roles for α2δ‐2 proteins in neurons. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric (FE) ceramic capacitors have attracted increasing attention for their excellent energy‐storage performance. However, it is extremely difficult to achieve desirable comprehensive energy‐storage features required for industrial applications. In this work, very high recoverable energy density Wrec ≈ 8.73 J cm–3, high efficiency η ≈ 80.1%, ultrafast discharge rate of <85 ns, and temperature‐insensitive high Wrec and η (Wrec ≈ 5.73 ± 4% J cm–3, η ≈ 75 ± 6%, 25–200 °C) are simultaneously obtained in 0.68NaNbO3‐0.32(Bi0.5Li0.5)TiO3 relaxor FE ceramics by introducing various polarization configurations in combination with microstructure modification. The structure mechanism for the excellent energy‐storage performance is disclosed by analyzing in situ structure evolution on multiple scales during loading/unloading by means of transmission electron microscopy and Raman spectroscopy. Both local regions consisting of different‐scale polar nanodomains and a nonpolar matrix, and local orthorhombic symmetry remaining with electric fields ensure a linear‐like polarization response within a wide field and temperature range owing to significantly delayed polarization saturation. The stabilization of orthorhombic FE phases rather than antiferroelectric orthorhombic phases in NaNbO3 after adding (Bi0.5Li0.5)TiO3 is also explored by means of X‐ray diffraction, dielectric properties, and selected area electron diffraction. In comparison with antiferroelectric ceramics, NaNbO3‐based relaxor FE ceramics provide a new solution to successfully design next‐generation pulsed power capacitors. [ABSTRACT FROM AUTHOR]

[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]

Calcium handling is vital to normal physiological function in the heart. Human atrial arrhythmias, eg. atrial fibrillation, are a major morbidity and mortality burden, yet major gaps remain in our understanding of how calcium signaling pathways function and interact. Inositol trisphosphate (IP3) is a Ca2+-mobilizing second messenger and its agonist-induced effects have been observed in many tissue types. In the atria IP3 receptors (IR3Rs) residing on junctional sarcoplasmic reticulum augment cellular Ca2+ transients and, when over-stimulated, lead to arrhythmogenesis. Recent studies have demonstrated that the predominant pathway for IP3 actions in atrial myocytes depends on stimulation of calcium-dependent forms of adenylyl cyclase (AC8 and AC1) by IP3-evoked Ca2+ release from the sarcoplasmic reticulum. AC8 shows co-localisation with IP3Rs and AC1 appears to be nearby. These observations support crosstalk between Ca2+ and cAMP pathways in nanodomains in atria. Similar mechanisms also appear to operate in the pacemaker region of the sinoatrial node. Here we discuss these significant advances in our understanding of atrial physiology and pathology, together with implications for the identification of potential novel targets and modulators for the treatment of atrial arrhythmias. [ABSTRACT FROM AUTHOR]

Calcium handling is vital to normal physiological function in the heart. Human atrial arrhythmias, eg. atrial fibrillation, are a major morbidity and mortality burden, yet major gaps remain in our understanding of how calcium signaling pathways function and interact. Inositol trisphosphate (IP3) is a calcium-mobilizing second messenger and its agonist-induced effects have been observed in many tissue types. In the atria IP3 receptors (IR3Rs) residing on junctional sarcoplasmic reticulum augment cellular calcium transients and, when over-stimulated, lead to arrhythmogenesis. Recent studies have demonstrated that the predominant pathway for IP3 actions in atrial myocytes depends on stimulation of calcium-dependent forms of adenylyl cyclase (AC8 and AC1) by IP3-evoked calcium release from the sarcoplasmic reticulum. AC8 shows co-localisation with IP3Rs and AC1 appears to be nearby. These observations support crosstalk between calcium and cAMP pathways in nanodomains in atria. Similar mechanisms also appear to operate in the pacemaker region of the sinoatrial node. Here we discuss these significant advances in our understanding of atrial physiology and pathology, together with implications for the identification of potential novel targets and modulators for the treatment of atrial arrhythmias. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric ceramics are good candidates for capacitor, sensor and actuator applications because of their high dielectric permittivity, high piezoelectric constant and high value of field induced strain, respectively. However, their dielectric loss is usually relatively high, which is a problem for actual applications. The introduction of the high entropy concept opens up the possibility of developing new multi-element relaxor-like ferroelectric materials with short-range ordered polar structures having short relaxation times to decrease their loss. Here we present a new high entropy A-site disordered perovskite (Pb 0.25 Ba 0.25 Sr 0.25 Ca 0.25)TiO 3 relaxor-like ferroelectric. Moreover, the ceramic has low loss (<0.015) from room temperature to 125 °C. The relaxor-like nature of the material is proved by dielectric and ferroelectric measurements. This work demonstrates the great potential of high entropy perovskites as relaxor-like ferroelectrics with a wide compositional window for tuning their properties for different applications. [ABSTRACT FROM AUTHOR]

Keywords: -adrenergic receptors; AKAPs; nanodomains; signaling EN -adrenergic receptors AKAPs nanodomains signaling 1 3 3 08/11/22 20220501 NES 220501 A Perspective on "Subcellular Propagation of Cardiomyocyte -Adrenergic Activation of Calcium... The least one expects from an anchor is to stay put (freely adapted from Salvador Dali's opinion about Alexander Calder's sculptures). Phosphorylation state-dependent interaction between AKAP7delta/gamma and phospholamban increases phospholamban phosphorylation. They show that the PLN-targeted intracellular 1AR-PKA-AKAP7 complex they recently identified[9] is endowed with considerable mobility, exceeding that of PLN itself. [Extracted from the article]

Plasmodesmata are intercellular pores connecting together most plant cells. These structures consist of a central constricted form of the endoplasmic reticulum, encircled by some cytoplasmic space, in turn delimited by the plasma membrane, itself ultimately surrounded by the cell wall. The presence and structure of plasmodesmata create multiple routes for intercellular trafficking of a large spectrum of molecules (encompassing RNAs, proteins, hormones and metabolites) and also enable local signalling events. Movement across plasmodesmata is finely controlled in order to balance processes requiring communication with those necessitating symplastic isolation. Here, we describe the identities and roles of the molecular components (specific sets of lipids, proteins and wall polysaccharides) that shape and define plasmodesmata structural and functional domains. We highlight the extensive and dynamic interactions that exist between the plasma/endoplasmic reticulum membranes, cytoplasm and cell wall domains, binding them together to effectively define plasmodesmata shapes and purposes. [ABSTRACT FROM AUTHOR]

In response to the invasion of microorganisms, plants actively balance their resources for growth and defence, thus ensuring their survival. The regulatory mechanisms underlying plant immunity and growth operate through complex networks, in which the brassinosteroid phytohormone is one of the central players. In the past decades, a growing number of studies have revealed a multi-layered crosstalk between brassinosteroid-mediated growth and plant immunity. In this Review, by means of the tango metaphor, we immerse ourselves into the intimate relationship between brassinosteroid and plant immune signalling pathways that is tailored by the lifestyle of the pathogen and modulated by other phytohormones. The plasma membrane is the unique stage where brassinosteroid and immune signals are dynamically integrated and where compartmentalization into nanodomains that host distinct protein consortia is crucial for the dance. Shared downstream signalling components and transcription factors relay the tango play to the nucleus to activate the plant defence response and other phytohormonal signalling pathways for the finale. Understanding how brassinosteroid and immune signalling pathways are integrated in plants will help develop strategies to minimize the growth–defence trade-off, a key challenge for crop improvement. [ABSTRACT FROM AUTHOR]

Gangliosides are glycosphingolipids consisting of a ceramide base and a bulky sugar chain that contains one or more sialic acids. This unique structure endows gangliosides with a strong tendency to self‐aggregate in solution, as well as in cellular membranes, where they can form nanoscopic assemblies called ganglioside nanodomains. As gangliosides are important biological molecules involved in a number of physiological processes, characterization of their lateral organization in membranes is essential. This review aims at providing comprehensive information about the nanoscale organization of gangliosides in various synthetic models. To this end, the impact of the hydrophobic backbone and the headgroup on the segregation of gangliosides into nanodomains are discussed in detail, as well as the way in which the properties of nanodomains are affected by ligand binding. Small size makes the characterization of ganglioside nanodomains challenging, and we thus highlight the biophysical methods that have advanced this research, such as Monte Carlo Förster resonance energy transfer, atomic force microscopy and approaches based on molecular diffusion. [ABSTRACT FROM AUTHOR]

The requirement for ferroelectric ceramics with a high Curie temperature and a high piezoelectric coefficient remains an important research task for high‐temperature sensors and actuators applications. (0.76‐x)BiFeO3‐0.24PbTiO3‐xBa(Sn0.2Ti0.8)O3 (BF‐PT‐BST) piezoelectric ceramics were fabricated using the solid‐state reaction method. XRD analysis indicated that the incorporation of large ionic radius Ba2+ at A‐site and nonferroelectric‐active Sn4+ at B‐site generated a decrease in the tetragonality degree c/a. A wide multiphase coexistence region was formed with the content of BST ranging from 0.13 to 0.28. The enhanced piezoelectric coefficient (d33 ~ 200pC/N) was achieved while maintaining a high Curie temperature (TC ~ 500°C) and a high depolarization temperature (Td ~ 450°C) for the composition of 0.6BF‐24PT‐0.16BST. TEM patterns provided clear evidence for the presence of nanodomains (~2nm) would be the predominant source for the enhanced piezoelectricity for the composition x = 0.20. The designed BF‐PT‐BST ternary system provides great potential for high‐temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]

In soft matter, thermal energy causes molecules to continuously translate and rotate, even in crowded environments, thereby impacting the spatial organization and function of most molecular assemblies, such as lipid membranes. Directly measuring the orientation and spatial organization of large collections (>3000 molecules μm−2) of single molecules with nanoscale resolution remains elusive. In this paper, we utilize SMOLM, single‐molecule orientation localization microscopy, to directly measure the orientation spectra (3D orientation plus "wobble") of lipophilic probes transiently bound to lipid membranes, revealing that Nile red's (NR) orientation spectra are extremely sensitive to membrane chemical composition. SMOLM images resolve nanodomains and enzyme‐induced compositional heterogeneity within membranes, where NR within liquid‐ordered vs. liquid‐disordered domains shows a ≈4° difference in polar angle and a ≈0.3π sr difference in wobble angle. As a new type of imaging spectroscopy, SMOLM exposes the organizational and functional dynamics of lipid‐lipid, lipid‐protein, and lipid‐dye interactions with single‐molecule, nanoscale resolution. [ABSTRACT FROM AUTHOR]

In soft matter, thermal energy causes molecules to continuously translate and rotate, even in crowded environments, thereby impacting the spatial organization and function of most molecular assemblies, such as lipid membranes. Directly measuring the orientation and spatial organization of large collections (>3000 molecules μm−2) of single molecules with nanoscale resolution remains elusive. In this paper, we utilize SMOLM, single‐molecule orientation localization microscopy, to directly measure the orientation spectra (3D orientation plus "wobble") of lipophilic probes transiently bound to lipid membranes, revealing that Nile red's (NR) orientation spectra are extremely sensitive to membrane chemical composition. SMOLM images resolve nanodomains and enzyme‐induced compositional heterogeneity within membranes, where NR within liquid‐ordered vs. liquid‐disordered domains shows a ≈4° difference in polar angle and a ≈0.3π sr difference in wobble angle. As a new type of imaging spectroscopy, SMOLM exposes the organizational and functional dynamics of lipid‐lipid, lipid‐protein, and lipid‐dye interactions with single‐molecule, nanoscale resolution. [ABSTRACT FROM AUTHOR]

Pseudobinary Gd 5 (Si,Ge) 4 compounds show a giant magnetocaloric effect due to an intriguing structure-magnetism interplay. Here, we report a high resolution transmission electron microscopic study of microstructure in a melt-grown compound of Gd 5 Si 1.5 Ge 2.5. Electron diffraction showed that mesoscopic microstructure of the compound consists of crystals of a monoclinic structure and two kinds of orthorhombic structure. However, atomic-level imaging revealed a coexistence of mosaic-like nanodomains of these structures in each crystal. The nanodomains have twin-like interfaces along the b axis of the crystal but have semicoherent interfaces along a perpendicular axis due to stacking faults. Such a nanoscale structural heterogeneity is due to covalent bond-controlled phase separation at elevated temperatures. This finding offers insights into phase relations and abnormal magnetic behavior of Gd 5 (Si,Ge) 4 compounds and points out a route of synthesizing bulk nanocomposites via nanoscale phase separation. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The nanoscale organization of biological membranes into structurally and compositionally distinct lateral domains is believed to be central to membrane function. The nature of this organization has remained elusive due to a lack of methods to directly probe nanoscopic membrane features. We show here that cryogenic electron micros-copy (cryo-EM) can be used to directly image coexisting nanoscopic domains in synthetic and bioderived membranes without extrinsic probes. Analyzing a series of single-component liposomes composed of synthetic lipids of varying chain lengths, we demonstrate that cryo-EM can distinguish bilayer thickness differences as small as 0.5 Å, comparable to the resolution of small-angle scattering methods. Simulated images from computational models reveal that features in cryo-EM images result from a complex interplay between the atomic distribution normal to the plane of the bilayer and imaging parameters. Simulations of phase-separated bilayers were used to predict two sources of contrast between coexisting ordered and disordered phases within a single liposome, namely differences in membrane thickness and molecular density. We observe both sources of contrast in biomimetic membranes composed of saturated lipids, unsaturated lipids, and cholesterol. When extended to isolatedmammalian plasma membranes, cryo-EM reveals similar nanoscale lateral heterogeneities. The methods reported here for direct, probe-free imaging of nanodomains in unperturbed membranes open new avenues for investigation of nanoscopic membrane organization. [ABSTRACT FROM AUTHOR]

Crystal structures and piezoelectric properties of PbZrO 3 -PbTiO 3 -Pb(Ni 1/3 Nb 2/3)O 3 ceramics near the triple point composition, particularly characteristics of the pseudocubic phase, were investigated. The pseudocubic phase, which formed near the triple point composition, disappeared with increase in the PbZrO 3 content. The pseudocubic phase had the Pm3m cubic structure. The tetragonal-pseudocubic morphotropic phase boundary (MPB) structure was developed during the tetragonal-to-cubic phase transformation. However, the rhombohedral phase directly transformed to the cubic phase because the structure of pseudocubic phase was similar to the rhombohedral structure. The specimens with pseudocubic phase and the specimens near pseudocubic phase exhibited nano-sized domains and small coercive electric fields, revealing their low domain wall energies. These specimens exhibited second-order ferroelectric-to-paraelectric phase transition and low Curie temperatures, confirming their low domain wall energies. The enhanced dielectric and piezoelectric properties of these specimens could be attributed to their low domain wall energies. [ABSTRACT FROM AUTHOR]

Anionic phospholipids, which include phosphatidic acid, phosphatidylserine, and phosphoinositides, represent a small percentage of membrane lipids. They are able to modulate the physical properties of membranes, such as their surface charges, curvature, or clustering of proteins. Moreover, by mediating interactions with numerous membrane-associated proteins, they are key components in the establishment of organelle identity and dynamics. Finally, anionic lipids also act as signaling molecules, as they are rapidly produced or interconverted by a set of dedicated enzymes. As such, anionic lipids are major regulators of many fundamental cellular processes, including cell signaling, cell division, membrane trafficking, cell growth, and gene expression. In this review, we describe the functions of anionic lipids from a cellular perspective. Using the localization of each anionic lipid and its related metabolic enzymes as starting points, we summarize their roles within the different compartments of the endomembrane system and address their associated developmental and physiological consequences. [ABSTRACT FROM AUTHOR]

Synaptic transmission and plasticity are shaped by the dynamic reorganization of signaling molecules within pre- and postsynaptic compartments. The nanoscale organization of key effector molecules has been revealed by single-particle trajectory (SPT) methods. Interestingly, this nanoscale organization is highly heterogeneous. For example, presynaptic voltage-gated calcium channels (VGCCs) and postsynaptic ligand-gated ion channels such as AMPA receptors (AMPARs) are organized into so-called nanodomains where individual molecules are only transiently trapped. These pre- and postsynaptic nanodomains are characterized by a high density of molecules but differ in their molecular organization and stability within the synaptic membrane. We review the main properties of these nanodomains, as well as the methods developed to extract parameters from SPT experiments. We discuss how such molecular dynamics influences synaptic transmission. The nanoscale organization of active synapses opens new insights into the dynamics and turnover of molecules as well as casting light on their contributions to signal transfer between individual neurons. Nanodomains are regions of transient aggregation and retention of diffusing receptors or channels. The shape of nanodomains changes in a timescale of hundreds of milliseconds to tens of minutes depending on their location in pre- or postsynaptic compartments, respectively. Many trajectories from SPT experiments allow identification of a nanodomain as a region where their displacement (velocity field) converges. The stability of nanodomains determines the residence times of channels and receptors, and contributes to the reliability of synaptic transmission. Nanodomains may shape nanocolumn alignment in the synaptic cleft. [ABSTRACT FROM AUTHOR]

Chemical doping is an indispensable tool to tailor the properties of the commercial piezoelectric materials. However, a high piezoelectric coefficient with enhanced thermal stability is rarely achieved by one dopant in some high-performance ferroelectrics, e.g., the recently discovered eco-friendly (Ba 0.85 Ca 0.15)(Zr 0.1 Ti 0.9)O 3 (BCZT) ceramics. In order to optimize the piezoelectric property in BCZT system by a simple way, we investigated the doping effect of Fe3+, Nb5+ and Bi3+ cations in BCZT ceramics respectively. The results indicate that only Nb5+-doped BCZT ceramics display a combination of large piezoelectric coefficient and enhanced thermal stability, compared with others. Moreover, the established phase diagrams and in-situ transmission electron microscope (TEM) observations reveal that such optimized piezoelectric properties after Nb5+ doping originates from (i) the low polarization anisotropy near the ambient tetragonal (T)-orthorhombic (O) phase transition and (ii) the easy domain wall motion of persistent miniaturized ferroelectric domains upon heating. [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]

Abstract X-ray diffraction (XRD) reciprocal space mapping (RSM) was used to investigate how nanograted electrodes affect the nanodomain distribution and average crystal structure in near-surface regions of poled Pb(Mg 1/3 Nb 2/3)O 3 -30%PbTiO 3 (PMN-30PT) single crystals. The RSM scans revealed a transverse broadening along the (H00) direction, which was quite different from that of either the rhombohedral (R) or monoclinic A (M A) phase. This broadening provides evidence of a non-uniform distribution of tilt angles between neighboring nanodomains, induced by a gradient in the applied electric field (E). Investigations of the front and back surfaces of the crystals revealed significant differences in the RSM scans. Gradients in the domain distribution and apparent symmetry may extend throughout the crystal thickness. The data evidence changes in the nanodomain distribution that results in adaptations of the average symmetry. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract A giant field-induced strain of 0.65% with excellent temperature insensitivity and fatigue resistance was achieved by introducing 1.5 mol.% B-site complex cations (Zn 1/3 Nb 2/3)4+ into the 0.93(Bi 1/2 Na 1/2)TiO 3 -0.07BaTiO 3 lead-free ferroelectric ceramics. (Bi 1/2 Na 1/2) 0.93 Ba 0.07 (Zn 1/3 Nb 2/3) x Ti 1- x O 3 (0 ≤ x ≤ 0.025) ceramics were prepared by the columbite route, their microstructure, electric properties, and field-induced strain behavior were systematically investigated. XRD analysis reveals that the B-site substitution by complex cations (Zn 1/3 Nb 2/3)4+ induces the phase transition from R 3 c to pseudocubic structures, and demonstrates different phase evolution under field applied. At the composition x = 0.015, a composition-driven boundary between the nonergodic state and ergodic state is observed. Meanwhile, the substitution by complex cations (Zn 1/3 Nb 2/3)4+ reduces the dimension of polar nanoregions (PNRs) due to the destruction of the long-range ferroelectric ordering. A phenomenological illustration based on Bokov's suggestion and Landau-Devenshire theory suggests the relationship between the size of PNRs and field-induced strain behavior. Graphical abstract Image 1 Highlights • A giant strain of 0.65% was achieved in (Zn 1/3 Nb 2/3)4+-doped 0.93BNT-0.07BT. • The boundary of nonergodic and ergodic states locates at x = 0.015. • The strain behavior is correlated to the formation energy of PNRs. [ABSTRACT FROM AUTHOR]

Abstract G protein-coupled receptors (GPCRs) are the largest family of membrane receptors and mediate the effects of a multitude of extracellular cues, such as hormones, neurotransmitters, odorants and light. Because of their involvement in numerous physiological and pathological processes and their accessibility, they are extensively exploited as pharmacological targets. Biochemical and structural biology investigations have clarified the molecular basis of GPCR signaling to a high level of detail. In spite of this, how GPCRs can efficiently and precisely translate extracellular signals into specific and well-orchestrated biological responses in the complexity of a living cell or organism remains insufficiently understood. To explain the high efficiency and specificity observed in GPCR signaling, it has been suggested that GPCR might signal in discrete nanodomains on the plasma membrane or even form stable complexes with G proteins and effectors. However, directly testing these hypotheses has proven a major challenge. Recent studies taking advantage of innovative optical methods such as fluorescence resonance energy transfer (FRET) and single-molecule microscopy have begun to dig into the organization of GPCR signaling in living cells on the spatial (nm) and temporal (ms) scales on which cell signaling events are taking place. The results of these studies are revealing a complex and highly dynamic picture, whereby GPCRs undergo transient interaction with their signaling partners, membrane lipids and the cytoskeleton to form short-lived signaling nanodomains both on the plasma membrane and at intracellular sites. Continuous exchanges among such nanodomains via later diffusion as well as via membrane trafficking might provide a highly sophisticated way of controlling the timing and location of GPCR signaling. Here, we will review the most recent advances in our understanding of the organization of GPCR signaling in living cells, with a particular focus on its dynamics. Highlights • GPCRs are the largest family of membrane receptors, mediating the effects of several hormones and neurotransmitters. • How GPCRs function in the complexity of an intact cell or organism to produce specific effects is insufficiently understood. • New microscopy methods allow investigating GPCR signaling in living cells with unprecedented spatiotemporal resolution. • Studies based on these methods have revealed signaling nanodomains on the plasma membrane and at intracellular sites. • GPCRs and other signaling proteins can rapidly enter or leave these nanodomains by lateral diffusion or membrane trafficking. [ABSTRACT FROM AUTHOR]

The domain structure formation in the congruent lithium tantalate single crystals after IR laser irradiation by linear scanning of Z + polar surface has been studied. Two types of domain structures have been revealed experimentally: self-similar structure and quasi-regular stripe structure. The statistical processing has shown that the increase in the scanning velocity leads to increase in the area with stripe domain structure and to decrease in the average domain period. At the maximum scanning velocity 4.8 m/s, the quasi regular domain stripe structure with average period 0.8 μm has been obtained over the 70% of the switched area. [ABSTRACT FROM AUTHOR]

Highlights • Membrane rafts have been proposed to be nm-sized, short-lived lipid-protein domains. • Methods that would allow visualizing such structures in vivo are only now beginning to emerge. • The raft concept maybe an oversimplification for a variety of nanostructures of heterogeneous sizes and functions. • It is wrong to equate rafts with detergent-resistant membrane fractions. • The term "raft" could be replaced with advantage by "nanodomain". Abstract The membrane raft hypothesis, proposed in 1997 by Simons and Ikonen, has played a paradoxical role in the history of biomembrane research. While it has generated a large amount of investigations, thus helping to increase our understanding of membranes, the object that gives name to the hypothesis, i.e. the raft itself, has been and still is an object of controversy, in which its very reality is often questioned. In this contribution I review the history of the hypothesis and its reception by membrane biologists, and summarize some of the valuable physico-chemical results that have been obtained while testing the raft hypothesis. To save a useful concept from its many misuses I propose that the expression "(transient) nanodomains" be employed instead of "rafts". [ABSTRACT FROM AUTHOR]