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Geometric confinement (GC) of skyrmions in nanodomains plays a crucial role in skyrmion stabilization. This confinement effect decreases the magnetic field necessary for skyrmion formation and is closely related to the applied mechanical stresses. However, the mechanism of GC is unclear and remains controversial. Here, we numerically study the effect of GC on skyrmion stabilization and find that zero Dzyaloshinskii–Moriya interaction (DMI) coupling constants imposed on the boundary surfaces of small thin plates cause confinement effects, stabilizing skyrmions in the low-field region. Moreover, the confined skyrmions are further stabilized by tensile strains parallel to the plate, and the skyrmion phase extends to the low-temperature region. This stabilization occurs due to the bulk anisotropic DMI coupling constant caused by lattice deformations. Our simulation data are qualitatively consistent with reported experimental data on skyrmion stabilization induced by tensile strains applied to a thin plate of the chiral magnet Cu 2 OSeO 3. • A geometric confinement (GC) model for skyrmions (SKY) is numerically studied. • Effect of GC on the SKY stabilization is confirmed. • The GC effect further improves the stabilization under uniaxial strains. • The combining effect increases the SKY area in the BT phase diagram. • The area increase is consistent with reported experimental data of Cu 2 OSeO 3. [ABSTRACT FROM AUTHOR]

Several human diseases are associated with a lack of caveolae. Yet, the functions of caveolae and the molecular mechanisms critical for shaping them still are debated. We show that muscle cells of syndapin III KO mice show severe reductions of caveolae reminiscent of human caveolinopathies. Yet, different from other mouse models, the levels of the plasma membrane-associated caveolar coat proteins caveolin3 and cavin1 were both not reduced upon syndapin III KO. This allowed for dissecting bona fide caveolar functions from those supported by mere caveolin presence and also demonstrated that neither caveolin3 nor caveolin3 and cavin1 are sufficient to form caveolae. The membrane-shaping protein syndapin III is crucial for caveolar invagination and KO rendered the cells sensitive to membrane tensions. Consistent with this physiological role of caveolae in counterpoising membrane tensions, syndapin III KO skeletal muscles showed pathological parameters upon physical exercise that are also found in CAVEOLIN3 mutation-associated muscle diseases.

As transport properties of doped ceria electrolytes depend significantly on the nature of the dopant and the defectivity, the design of new materials and devices requires proper understanding of the defect structure. Among lanthanide dopants, Yb shows some peculiar characteristics that call for a possible different defect structure compared to Gd and Sm conventional dopants, which could be linked to its poorer performance. For this purpose, we combine synchrotron and neutron powder diffraction exploiting the Rietveld and Pair distribution Function. By increasing its concentration, Yb produces qualitatively the same structural distortions as other dopants, leading to a domain structure involving the progressive nucleation and growth of nanodomains with a Yb2O3-like (C-type) structure hosted in a fluorite CeO2 matrix. However, when it comes to growing the C-type nanodomains into a long-range phase, the transformation is less pronounced. At the same time, a stronger structural distortion occurs at the local scale, which is consistent with the segregation of a large amount of oxygen vacancies. The strong trapping of VOs by Yb3+ explains the poor performance of Yb-doped ceria with respect to conventional Sm-, Gd-, and Y-doped samples at equal temperature and dopant amount.

The mechanisms behind the high piezoelectricity of (K,Na)NbO 3 -based lead-free ceramics were investigated, including electric field-induced phase transitions and composition-driven nanodomains. The construction of a rhombohedral-tetragonal (R-T) phase boundary, confirmed using several advanced techniques, allowed a large piezoelectric constant ( d 33 ) of 450 ± 5 pC/N to be obtained in (1- x )K 0.4 Na 0.6 Nb 0.945 Sb 0.055 O 3 - x Bi 0.5 Na 0.5 (Hf 1- y Sn y )O 3 (0 ≤ x ≤ 0.06 and 0 ≤ y ≤ 0.5) ceramics possessing an ultralow Δ U T-R of 7.4 meV. More importantly, the existence of an intermediate phase, i.e., the electric-induced phase (EIP), bridging the rhombohedral R [ P s //(111)] and tetragonal T [ P s //(001)] phases during the polarization rotation was demonstrated. Striped nanodomains (∼40 nm) that easily responded to external stimulation were also observed in the ceramics with an R-T phase. Thus, the enhanced piezoelectric properties originated from EIP and the striped nanodomains. [ABSTRACT FROM AUTHOR]

The perovskite structured lead-free system Na 0.5 Bi 0.5 TiO 3 (NBT) whiskers were synthesized from whiskers of layered tunnel structured Na 2 Ti 6 O 13 (NT), using a topochemical route. Both NT and NBT whiskers show high aspect ratios with an average length of 15 µm and diameter of 1 µm. By prolonging the reaction time from 2 h to 6 h at 900 °C, NT whiskers with monoclinic phase completely transformed to NBT whiskers with pseudocubic phase. Typical strip-like nanodomains are observed in a NBT whisker, which are parallel to each other. The piezoelectric response amplitude for a NBT whisker indicates a large electric field induced strain, corresponding to a S max / E max value of as high as 300 pm/V. This work provides an in-depth instruction to prepare pure NBT whiskers, and gives the detailed piezoelectricity of NBT whiskers to promote their applications in energy harvesting and micro-electromechanical systems. [ABSTRACT FROM AUTHOR]

Ever since technologies enabled the characterisation of eukaryotic plasma membranes, heterogeneities in the distributions of its constituents were observed. Over the years this led to the proposal of various models describing the plasma membrane organisation such as lipid shells, picket-and-fences, lipid rafts, or protein islands, as addressed in numerous publications and reviews. Instead of emphasising on one model we in this review give a brief overview over current models and highlight how current experimental work in one or the other way do not support the existence of a single overarching model. Instead, we highlight the vast variety of membrane properties and components, their influences and impacts. We believe that highlighting such controversial discoveries will stimulate unbiased research on plasma membrane organisation and functionality, leading to a better understanding of this essential cellular structure.

[Display omitted] • The microstructural evolution of Ni 54 Ti 46 alloy is investigated. • The lattice instability leads to the storage modulus anomaly in Ni 54 Ti 46 alloy. • Strain glass transition occurs in the B2 matrix of Ni 54 Ti 46 alloy. Highly Ni-rich NiTi alloys have attracted interest due to their unique mechanical and functional properties. Most research on these alloys has focused on mechanical properties under heat treatment. Here, we investigate the dynamic mechanical characteristics and microstructural evolution of the B2 matrix in Ni 54 Ti 46 alloy. The findings demonstrate that softening in storage modulus is accompanied by the successive formation and constrained growth of nanodomains over a wide temperature range, indicating a strain glass transition occurs in the B2 matrix of Ni 54 Ti 46 alloy. [ABSTRACT FROM AUTHOR]

Large magnetostriction with low saturation magnetic field was recently reported in Fe-Pd ferromagnetic strain glass alloys. Such behaviour is highly desirable for miniaturized sensor and actuator applications. The origin of high performance magnetostriction in Fe-Pd ferromagnetic strain glass is suggested to stem from its martensitic nanodomains. However, the atomic formation mechanism underlying these nanodomains and their associated local crystal symmetry breaking have not been well revealed. Moreover, accumulating experimental results indicate that the nano-structure can lead to a small saturation field but cannot guarantee large magnetostriction. Consequently, the necessary conditions for low field triggered large magnetostriction of Fe-Pd ferromagnetic strain glass alloys still remain unclear. In this paper, the chemistry, structure and transformation properties of the Fe 98- x Cu 2 Pd x (x = 28.5 ∼ 31) system are systematically explored to discover the origin of the high performance magnetostriction of ferromagnetic strain glass alloys. We found that the structure of ferromagnetic strain glass consists of local chemical order. This leads to tetragonal martensitic nanodomains with the local crystal symmetry breaking. The local chemical order also induces strong local phonon softening and a low modulus during the strain glass transition. Further investigation shows that the combination of martensitic nanodomains and low modulus are the necessary conditions to achieve both large magnetostriction and a low saturation field, because they can result in small energy barriers for the rotation of nanodomains. These findings provide an effective guideline to design high performance magnetostrictive materials and devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Rapid release of calcium from internal stores via ryanodine receptors (RyRs) is one of the fastest types of cytoplasmic second messenger signalling in excitable cells. In the heart, rapid summation of the elementary events of calcium release, 'calcium sparks', determine the contraction of the myocardium. We adapted a correlative super-resolution microscopy protocol to correlate sub-plasmalemmal spontaneous calcium sparks in rat right ventricular myocytes with the local nanoscale RyR2 positions. This revealed a steep relationship between the integral of a calcium spark and the sum of the local RyR2s. Segmentation of recurring spark sites showed evidence of repeated and triggered saltatory activation of multiple local RyR2 clusters. In myocytes taken from failing right ventricles, RyR2 clusters themselves showed a dissipated morphology and fragmented (smaller) clusters. They also featured greater heterogeneity in both the spark properties and the relationship between the integral of the calcium spark and the local ensemble of RyR2s. While fragmented (smaller) RyR2 clusters were rarely observed directly underlying the larger sparks or the recurring spark sites, local interrogation of the channel-to-channel distances confirmed a clear link between the positions of each calcium spark and the tight, non-random clustering of the local RyR2 in both healthy and failing ventricles.

Nanoparticles of TiO 2 are used in a variety of applications because of their high refractive index and photocatalytic behaviour. We report that both the interactions between the surfactant and titanium alkoxide and templating provided by a microemulsion significantly retard the formation of visible TiO 2 aggregates. TiO 2 nanoparticles (<30 nm) were prepared under mild, neutral conditions within water-in-oil and bicontinuous silicone microemulsions. The particles aggregated only slowly, as shown by UV absorption spectroscopy transmission electron microscopy, and particle sizing. Retarded particle growth is ascribed primarily to constricted domains provided by self-organization within a water/surfactant/silicone microemulsion. [ABSTRACT FROM AUTHOR]

Characteristics of the strain glass transition exhibited in as-quenched and 250 °C 1–5 h aged Ti 48.7 Ni 51.3 SMA were studied by various tests/measurements. The results of frequency-dependent storage modulus vs. temperature measurement, the temperature-dependent resistivity, thermal conductivity, and specific heat tests demonstrated the signature and characteristics of the strain glass transition exhibited in as-quenched and 250 °C early-aged Ti 48.7 Ni 51.3 SMA. The plate-/disk-like morphology and spatially heterogeneous distribution of the real Ni-rich nanodomains in as-quenched and 250 °C 1–5 h aged specimens were quantitatively characterized using small-angle X-ray scattering (SAXS) technique. The formative origin of the real nanodomains and the relationship between the real nanodomains and the strain nanodomains are proposed accordingly. Experimental results indicated R-like phase and Ti 3 Ni 4 -like precipitates co-existing in the strain glass of 250 °C early-aged specimens, and they also demonstrated the growth behavior of the real nanodomains exhibited in specimens during thermal aging. It was also found that increasing the aging time can elevate the T g from ∼−60 °C to ∼−20 °C, which indicates the tunable characteristic of T g for as-quenched Ti 48.7 Ni 51.3 SMA. [ABSTRACT FROM AUTHOR]

Imaging of ferroelectric domains using scanning electron microscopy is challenging as ferroelectrics are usually highly insulating. However, micro and nanodomain patterns can be directly visualized in secondary electrons using proper parameters. Low accelerating voltage or local charge compensation allows visualizing isolated domains with sizes above 100 nm without any sample preparation. Nanodomain patterns can be visualized with resolution about 3 nm after proper preparation of the sample surface: controlled chemical etching to obtain nanoscale surface relief and subsequent covering of the crystal surface by conductive film. Features of visualization of various nanodomain structures by scanning electron microscopy are considered. [ABSTRACT FROM PUBLISHER]

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) is a sustainable material for thin-film photovoltaics with device efficiencies greater than 12% have been demonstrated. Despite similar crystal structure and polycrystalline film microstructures, there is widespread evidence for larger-amplitude potential and bandgap fluctuations in CZTS than in the analogous Cu(In,Ga)Se2 (CIGSe) chalcopyrite material. This disorder is believed to account for a sizable part of the larger open-circuit voltage ( VOC) deficit in CZTS devices, yet the detailed origins and length scales of these fluctuations have not been fully elucidated. Herein, we present a transmission electron microscopy study focusing on composition variation within bulk multicrystals of CZTS grown by the travelling heater method (THM). In these slow-cooled, solution grown crystals we find direct evidence for spatial composition fluctuations of amplitude <1 at.% (∼5 × 1020 cm−3) and thus, explainable by point defects. However, rather than being homogeneously-distributed we find a characteristic 20 nm length scale for these fluctuations, which sets a definite length scale for band gap and potential fluctuations. At Σ3 grain boundaries, we find no evidence of composition variation compared to the bulk. The finding highlights such variations reported at grain boundaries in polycrystalline thin-films are direct consequences of processing methods and not intrinsic properties of CZTS itself. [ABSTRACT FROM AUTHOR]

Sr 4 BiRTi 4 Nb 6 O 30 (R = Sm, Eu) ceramics with tetragonal tungsten bronze structure were prepared by the conventional solid state reaction method. The crystalline structure, microstructure, dielectric and ferroelectric properties of the ceramics were investigated. Structural analysis using the powder x-ray diffraction patterns revealed the formation of tetragonal tungsten bronze structure in space group P 4 bm . Columnar grains with a homogeneous distribution were formed in Sr 4 BiEuTi 4 Nb 6 O 30 ceramics, while in Sr 4 BiSmTi 4 Nb 6 O 30 ceramics the microstructure became inhomogeneous and some abnormal grains were also formed. The dielectric properties of the ceramics exhibited relaxor type phase transition which can be attributed to the random distribution of Bi and Sm/Eu ions at A1-sites and Ti and Nb ions at the B-sites of the TTB structure. The peak temperature shifted towards the higher temperatures and the magnitude of the dielectric constant decreased with increasing frequency. Moreover, the temperature of the dielectric maximum T m increased as the radius of the R ion getting decreased. From the P-E hysteresis loops, remnant polarization of 0.83 μC/cm 2 and 0.6 μC/cm 2 were obtained for Sr 4 BiEuTi 4 Nb 6 O 30 and Sr 4 BiSmTi 4 Nb 6 O 30 , respectively. [ABSTRACT FROM AUTHOR]

Formation of the micro- and nanodomain structures in congruent lithium tantalate single crystal under the action of pyroelectric field induced by pulse infrared laser irradiation at elevated temperatures was investigated. Three types of the self-organized domain structures were obtained: (1) the self-similar domain structure formed in crystal regions heated below Curie temperature, (2) the maze-type domain structure, and (3) irregular-shaped isolated domains formed in the regions heated above Curie temperature. The results of calculation of the time dependent spatial distribution of the temperature and pyroelectric field have been used for explanation of the peculiarities of domain structure formation. [ABSTRACT FROM AUTHOR]

We show that in layered oxides that are employed as cathodes in lithium-ion batteries, the cation layers can order on different {111} NaCl planes within a single particle, which makes the lithium layer discontinuous across a particle. The findings challenge previous assertions that lithium undergoes 2-D diffusion in layered oxides and the data provide new insights into the decrease in rate capabilities for some layered oxides. Therefore, it is critically important to understand how these discontinuities form and how the loss of 2-D diffusion impacts the overall performance of the layered oxide cathode materials. Employing X-ray diffraction (XRD) and aberration-corrected scanning transmission electron microscopy (STEM), we find that as the material transitions from a disordered to an ordered state, it forms four orientation variants corresponding to the four {111} NaCl planes. This transition is not intrinsic to all layered oxides and appears to be more strongly affected by nickel. Furthermore, with energy dispersive spectroscopy (EDS), we show that there is an increase in the nickel concentration at the interface between each orientation variant. This reduces the rate of lithium diffusion, negatively affects the rate capability, and could be contributing to the overall capacity fade. [ABSTRACT FROM AUTHOR]

At room temperature, 0.46PIN-0.23PMN-0.33PT single crystals with compositions near the morphotropic phase boundary (MPB) can be induced ferroelectric phase transition by applying an electric field along the direction of [001]c, and the phase change can also explain the origin of the excellent piezoelectric properties of the relaxation ferroelectric single crystal. In the phase boundary components, relaxation properties of single crystal and possible phase structure cause the structure of heterogeneity and uncertainty, and in the process of domain engineering, domain induced polarization rotation and the metastable phase, such as photograph, monoclinic which play an important role on the characteristics of piezoelectric materials. Firstly, the local lattice structure and phase transitions of unpoled 0.24PIN-0.43PMN-0.33PT single crystal were studied by Micro-Raman spectroscopy at room temperature. A total of 11 Raman active modes were ascertained using the Gauss line shape approximation, which deduces that 0.43PIN- 0.26PMN-0.33PT single crystal with morph tropic phase boundary (MPB) composition has monoclinic symmetry. Then MB-MC monoclinic phase transition induced by electric field was studied, from the point of view of energy, the Mc monoclinic phase structure is more stable than MB monoclinic phase structure. [ABSTRACT FROM AUTHOR]

A polystyrene- block-polyisoprene ((PS- b-PI)) star polymer was synthesized by photochemical reversible addition fragmentation chain transfer (RAFT) polymerization. The obtained star polymer was epoxidized and used as a toughening agent in an epoxy thermoset. The incorporation of the epoxidized star polymer resulted in the formation of nanostructures and it was fixed by a crosslinking reaction. The formation of nanostructures in the thermosets follows the mechanism of reaction-induced microphase separation. The mechanical properties such as toughness and tensile strength were considerably increased due to the nanostructures formed by reactive blending. [ABSTRACT FROM AUTHOR]

The role of oxygen atoms in the α″ martensite phase was investigated in the Ti-20 at.% Nb alloy by X-ray diffractometry and differential scanning calorimetry. The axial ratio b / a of α″ martensite and reverse martensitic transformation temperature increased with increasing oxygen content. These results imply that the α″ martensite was stabilized by oxygen atoms, owing to the relaxation of the strain field introduced by the oxygen atoms. [ABSTRACT FROM AUTHOR]

Through a combination of experiments and MD simulations, x w = 0.25 is a turnover point from homogeneity to heterogeneity for the [C 2 mim][Tf 2 N]/water mixtures. The microenvironment changes were further analyzed through RDFs, statistical function, interstice model and density profile. At x w = 0.25 the microstructures of [C 2 mim][Tf 2 N]/water can be used as some soft templates. [Display omitted] • The microstructures of [C 2 mim][Tf 2 N]/water mixtures were explored by experiments and MD simulations. • Using the interstice model and molecular intrinsic characteristic contour, the interstices were analyzed. • x w = 0.25 is a turnover point near the phase separation point, and large aggregations are formed. • Interface analyses were discussed. Ionic liquid (IL)/water mixtures with specified structures can aggregate or assemble in solutions to form clusters, which can be widely used as templates in the design and preparation of functional materials. However, microstructures with different water contents remain unclear, especially near the phase boundary. Herein, we explored the effects of water on the structure of a hydrophobic IL, [C 2 mim][Tf 2 N], and proposed the formation of nanodomains as the composition approached phase separation points through the combination of experiments, molecular dynamics, and statistical analyses. Results show that x w = 0.25 is a turnover point near the phase boundary, and some aggregations among water molecules, cations, and anions gradually begin to form two phase regions. Below x w = 0.25, the mixtures are a uniformly dispersed system, and the interstices formed between [C 2 mim]+ and [Tf 2 N]− can only accommodate the water monomer. When x w > 0.25, density profiles show that [C 2 mim][Tf 2 N] makes a distinct boundary with water molecules. The analyses of the microstructure and size of nanodomains in this work may provide a theoretical basis and new strategy for improving the design of soft templates for porous materials. [ABSTRACT FROM AUTHOR]

With dynamic mechanical analysis, magnetism measurement and microstructure characterization, the elastic modulus anomaly in a Fe-Mn-Cr-C cryogenic steel was investigated to clarify the correlation of magnetic transition with lattice instability and microstructural evolution. It was found that the elastic modulus begins to decrease abnormally at temperatures higher than the critical temperature of the paramagnetic-antiferromagnetic transition and a noticeable drop of elastic modulus occurs around the Neel temperature upon cooling. These findings suggest that the elastic modulus anomaly is closely associated with lattice instability across a large temperature range and that the paramagnetic-antiferromagnetic transition worsens the lattice instability. Meticulous microstructure characterizations show that during the elastic modulus anomaly the nanodomains with the body-centered tetragonal structure emerge, providing the evidence for the lattice instability of the austenite in the Fe-Mn-Cr-C steel. [Display omitted] [ABSTRACT FROM AUTHOR]

To promote infections, pathogens exploit host cell machineries such as structural elements of the plasma membrane. Studying these interactions and identifying molecular players are ideal for gaining insights into the fundamental biology of the host cell. Here, we used the anthrax toxin to screen a library of 1,500 regulatory, cell-surface, and membrane trafficking genes for their involvement in the intoxication process. We found that endoplasmic reticulum (ER)-Golgi-localized proteins TMED2 and TMED10 are required for toxin oligomerization at the plasma membrane of human cells, an essential step dependent on localization to cholesterol-rich lipid nanodomains. Biochemical, morphological, and mechanistic analyses showed that TMED2 and TMED10 are essential components of a supercomplex that operates the exchange of both cholesterol and ceramides at ER-Golgi membrane contact sites. Overall, this study of anthrax intoxication led to the discovery that lipid compositional remodeling at ER-Golgi interfaces fully controls the formation of functional membrane nanodomains at the cell surface. [Display omitted] • Anthrax intoxication requires the p24 protein family members TMED2 and TMED10 • TMEDs maintain lipid transfer protein complexes at endoplasmic reticulum (ER)-Golgi membrane contacts • ER-Golgi MCSs control cell-surface lipid nanodomain formation Anwar et al. show that organization of the plasma membrane into nanodomains, which are required for anthrax intoxication, depends on the transfer of cholesterol at sites where the endoplasmic reticulum and the Golgi contact each other. This transfer depends on a protein supercomplex that is organized by two proteins, TMED2 and TMED10. [ABSTRACT FROM AUTHOR]

Phase boundary engineering (PBE) has remarkably enhanced the piezoelectric properties of potassium sodium niobate {(K, Na)NbO 3 , KNN} piezoceramics, yet the physical mechanisms need to be further understood. Here we outline a new physical phenomenon to describe piezoelectricity enhancement in KNN-based ceramics with PBE. We propose that the enhancement is due to the multi-phase coexistence featured with strong relaxation behavior. The strong relaxation behavior was unambiguously revealed by cryogenic experiments and originated from the polar nanoregions (PNRs) exhibiting a scale of 2.1 nm and a weak tetragonality (c/a = 1.0040). in situ temperature-dependent experiments uncovered the thermal evolution of the ferroelectric matrix and PNRs in both unpoled and poled samples, the first report in KNN-based ceramics. Our experiments combined with phenomenological theory revealed that ultra-fine nanodomains, PNRs, and easy polarization rotation together promote macro dielectric and piezoelectric properties in the relaxation-featured multi-phase coexistence. This work reveals the physical mechanism from different levels (e.g., local-mesoscopic-macroscopic), thus providing a new systematic understanding of the observed enhancement of piezoelectricity. Proposing a new physical mechanism, relaxor-featured multi-phase coexistence, to explain piezoelectricity enhancement in potassium sodium niobate-based ceramics. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of electron cryomicroscopy (cryo-EM) has evolved immensely in the last several decades and is now well-established in the analysis of protein structure both in isolation and in their cellular context. This review focuses on the history and application of cryo-EM to the analysis of membrane architecture. Parallels between the levels of organization of protein structure are useful in organizing the discussion of the unique parameters that influence membrane structure and function. Importantly, the timescales of lipid motion in bilayers with respect to the timescales of sample vitrification is discussed and reveals what types of membrane structure can be reliably extracted in cryo-EM images of vitrified samples. Appreciating these limitations, a review of the application of cryo-EM to examine the lateral organization of ordered and disordered domains in reconstituted and biologically derived membranes is provided. Finally, a brief outlook for further development and application of cryo-EM to the analysis of membrane architecture is provided., (© 2023 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society and the Royal Society of Biology.)

This is the first in a series of papers considering elastic scattering from laterally heterogeneous lipid vesicles containing multiple domains. Unique among biophysical tools, small-angle neutron scattering can in principle give detailed information about the size, shape and spatial arrangement of domains. A general theory for scattering from laterally heterogeneous vesicles is presented, and the analytical form factor for static domains with arbitrary spatial configuration is derived, including a simplification for uniformly sized round domains. The validity of the model, including series truncation effects, is assessed by comparison with simulated data obtained from a Monte Carlo method. Several aspects of the analytical solution for scattering intensity are discussed in the context of small-angle neutron scattering data, including the effect of varying domain size and number, as well as solvent contrast. The analysis indicates that effects of domain formation are most pronounced when the vesicle's average scattering length density matches that of the surrounding solvent. [ABSTRACT FROM AUTHOR]

The strain glass transition has been found in many ferroelastic systems, but the microstructural nature of strain glass is still unclear. Here, two-dimensional second and fourth order moment invariants as well as image entropy are used to evaluate the presence of a strain-glass state in simulated microstructure images of a doped ferroelastic system. Four different microstructural states are identified, depending on the doping concentration of point defects and the temperature. The martensitic state is characterized by a broad moment invariant distribution peaking near the invariants for the circle, whereas systems that display the strain glass transition produce distinctly different distributions. The image entropy is found to increase with increasing defect concentration; above the critical defect concentration of 0.1, image entropy becomes nearly linearly dependent on temperature. The image analysis approach is capable of characterizing the range of strain domain shapes that occur in the different microstructural states of a doped ferroelastic system. [ABSTRACT FROM AUTHOR]

Formation of nanodomain structures during cooling after pulse heating by infrared laser has been studied in congruent lithium tantalate (CLT) and lithium niobate (CLN) single crystals.In situstudy of the domain structure evolution allowed to reveal that in CLN the isolated domains appeared at the edges of the irradiated zone and grew to the center. In contrast, the quasi-regular stripe domain structure appeared in CLT near the edge of irradiated zone. The difference has been attributed to lower Curie temperature and larger pyroelectric coefficient of CLT. The self-organized domain structures can be used for periodical poling with submicron periods. [ABSTRACT FROM AUTHOR]

A group-theoretical analysis was carried out to determine the possible orientation states of domains formed as a result of the `perovskite-brownmillerite' phase transition in SrCo0.8Fe0.2O2.5 oxide with mixed ion-electron conductivity (MIEC). The results of the theoretical analysis agree with the experimental data obtained in the study of the SrCo0.8Fe0.2O2.5 microstructure by means of transmission electron microscopy. Brownmillerite SrCo0.8Fe0.2O2.5 (BM) has a lamellar texture composed of 90° twins 60-260 nm in size; the 〈010〉BM and 〈101〉BM directions are linked through twinning in accordance with the predictions of the group-theoretical analysis. The presence of twins and their switching under mechanical load provide evidence that the perovskite-brownmillerite phase transition in SrCo0.8Fe0.2O2.5 is ferroelastic. Comparative analysis of the phenomena observed for ferroelectrics and MIEC oxides indicates their similarity based on the common nature of ferroelectricity and ferroelasticity, and allows us to suppose that nonstoichiometric SrCo0.8Fe0.2O3−δ with compositional disorder may be considered (in terms of its microstructural features) a `relaxor ferroelastic'. [ABSTRACT FROM AUTHOR]

Invented in the 1990s, near-field optical microscopy (NSOM) was the first optical microscopy method to hold the promise of finally breaking the diffraction barrier in studies of biological samples. This promise, though, failed to materialize at that time, largely owing to the inability to image soft samples, such as cell surfaces, without damage. However, steady technical improvements have now produced NSOM devices that can routinely achieve images of cell surfaces with sub-100 nm resolution in aqueous solution. Further, beyond just optical information, these instruments can also provide simultaneous topographic, mechanical, and/or chemical details of the sample, an ability not yet matched by any other optics-based methodology. With the long recognized important roles of many biological processes at cell surfaces in human health and disease, near-field probing of cell surfaces is indeed now well poised to directly illume in biomedicine what has, until recently, been unknowable with classic light microscopy. From the Clinical Editor This paper presents a novel and important near-field microscopy-based method directly enabling the imaging of cell surfaces with sub-100nm resolution. Unlike other optics-based methods, the presented technique can also provide topographic, mechanical and chemical details of the samples. [ABSTRACT FROM AUTHOR]

Candida albicans is an opportunistic pathogen. It adheres to mammalian cells through a variety of adhesins that interact with host ligands. The spatial organization of these adhesins on the cellular interface is however poorly understood, mainly because of the lack of an instrument able to track single molecules on single cells. In this context, the atomic force microscope (AFM) makes it possible to analyze the force signature of single proteins on single cells. The present study is dedicated to the mapping of the adhesive properties of C. albicans cells. We observed that the adhesins at the cell surface were organized in nanodomains composed of free or aggregated mannoproteins. This was demonstrated by the use of functionalized AFM tips and synthetic amyloid forming/disrupting peptides. This direct visualization of amyloids nanodomains will help in understanding the virulence factors of C. albicans . From the Clinical Editor The present study reports on the successful atomic force microscopy-based mapping of the adhesive properties of C. albicans cells, an accomplishment that highlights the utility of AFM. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrathin Ni-Co nanosheets were incorporated in Pebax matrix to fabricated MMMs. • Ni and Co metal on Ni-Co-NS constituted disparate-CO 2 -affinity nanodomains in MMMs. • Disparate-CO 2 -affinity nanodomains facilitated quickly CO 2 transport in MMMs. • MMMs showed CO 2 permeability of 483 Barrer and CO 2 /CH 4 selectivity of 39. One of the biggest challenges of Pebax-based membranes is how to simultaneously achieve high CO 2 permeability and selectivity. Hence, mixed matrix membranes (MMMs) were designed and fabricated by incorporating the ultrathin Ni-Co nanosheet (Ni-Co-NS) fillers into Pebax® MH 1657 (Pebax) matrix to improve CO 2 separation performance. The ultrathin Ni-Co-NS fillers had disparate-CO 2 -affinity nanodomains and were endowed with three main functions in the Pebax/Ni-Co-NS MMMs: i) First, Ni and Co metals constituted CO 2 -philic and non-CO 2 -philic nanodomains, respectively, because the two metals had disparate CO 2 adsorption enthalpy. CO 2 -philic nanodomains rendered a high affinity capacity, whereas non-CO 2 -philic nanodomains rendered low-friction diffusion. Thus, a combination of the disparate-CO 2 -affinity nanodomains significantly facilitated CO 2 transport. ii) Second, the pore size of the nanosheets decreased from 0.79 nm to 0.49 nm by introducing the second Co metal into Ni-NS, and the decreased pores size contributed to strengthen CO 2 /CH 4 selectivity. iii) Third, the uniform nanopores of Ni-Co-NS that paralleled to the gas concentration gradient constituted high-speed CO 2 transport channels, which was conducive to improving CO 2 permeability of MMMs. Therefore, CO 2 separation performance of MMMs was remarkably improved by Ni-Co-NS fillers. Pebax/Ni-Co-NS MMMs with the content of 5 wt% Ni-Co-NS fillers showed the highest CO 2 permeability of 483 ± 11 Barrer and CO 2 /CH 4 selectivity of 39 ± 1.1. It implies that the introduction of nanosheets with two different metals is an effective method to fabricate MMMs with an excellent CO 2 separation performance. [ABSTRACT FROM AUTHOR]

We report a first-principles density functional theory study on the interaction of interstitial O atoms in body-centered cubic β -Ti 3 Nb alloy, the lattice distortion induced by O and its effect on the β to α ″ transformation. Our calculations demonstrate strong repulsion between O atoms in general, but also reveal a weak attraction at an O–O separation of around 5.63 Å ( 3 a ), which corresponds to a Ti 6 Nb 2 O structure. At low concentration (Ti 96 Nb 32 O), O induces a local α ″-like structure in β -Ti 3 Nb lattice, albeit to the extent of the nearest- and next-nearest neighbors, and exerts either a remarkable (6–8 meV atom −1 ) or a negligible (0–1 meV atom −1 ) energy barrier to the β to α ″ transformation, dependent on the orientation of its elastic dipole with respect to the external stress. At high concentration (Ti 6 Nb 2 O), interstitial O atoms give rise to the shuffling of neighboring {1 1 0} planes along the 〈 1 1 ¯ 0 〉 direction and generate a semi- α ″ structure, which is believed to be the nanodomain structure observed in experiment by Miyazaki and co-workers. In both cases, O brings up suppression effect on the β to α ″ transformation. [ABSTRACT FROM AUTHOR]