Engineering Relaxor Behavior in (BaTiO ) /(SrTiO ) Superlattices.

Complex-oxide superlattices provide a pathway to numerous emergent phenomena because of the juxtaposition of disparate properties and the strong interfacial interactions in these unit-cell-precise structures. This is particularly true in superlattices of ferroelectric and dielectric materials, wherein new forms of ferroelectricity, exotic dipolar textures, and distinctive domain structures can be produced. Here, relaxor-like behavior, typically associated with the chemical inhomogeneity and complexity of solid solutions, is observed in (BaTiO ) /(SrTiO ) (n = 4-20 unit cells) superlattices.

A novel active transposon creates allelic variation through altered translation rate to influence protein abundance.

Protein translation is tightly and precisely controlled by multiple mechanisms including upstream open reading frames (uORFs), but the origins of uORFs and their role in maize are largely unexplored. In this study, an active transposition event was identified during the propagation of maize inbred line B73. The transposon, which was named BTA for 'B73 active transposable element hAT', creates a novel dosage-dependent hypomorphic allele of the hexose transporter gene ZmSWEET4c through insertion within the coding sequence in the first exon, and results in reduced kernel size.

A cost-effective tsCUT&Tag method for profiling transcription factor binding landscape.

Knowledge of the transcription factor binding landscape (TFBL) is necessary to analyze gene regulatory networks for important agronomic traits. However, a low-cost and high-throughput in vivo chromatin profiling method is still lacking in plants. Here, we developed a transient and simplified cleavage under targets and tagmentation (tsCUT&Tag) that combines transient expression of transcription factor proteins in protoplasts with a simplified CUT&Tag without nucleus extraction.

Thin-Film Ferroelectrics.

Over the last 30 years, the study of ferroelectric oxides has been revolutionized by the implementation of epitaxial-thin-film-based studies, which have driven many advances in the understanding of ferroelectric physics and the realization of novel polar structures and functionalities. New questions have motivated the development of advanced synthesis, characterization, and simulations of epitaxial thin films and, in turn, have provided new insights and applications across the micro-, meso-, and macroscopic length scales. This review traces the evolution of ferroelectric thin-film research through the early days developing understanding of the roles of size and strain on ferroelectrics to the present day, where such understanding is used to create complex hierarchical domain structures, novel polar topologies, and controlled chemical and defect profiles.

Exploring the Pb Sr HfO System and Potential for High Capacitive Energy Storage Density and Efficiency.

The hafnate perovskites PbHfO (antiferroelectric) and SrHfO ("potential" ferroelectric) are studied as epitaxial thin films on SrTiO (001) substrates with the added opportunity of observing a morphotropic phase boundary (MPB) in the Pb Sr HfO system. The resulting (240)-oriented PbHfO (Pba2) films exhibited antiferroelectric switching with a saturation polarization ≈53 µC cm at 1.6 MV cm , weak-field dielectric constant ≈186 at 298 K, and an antiferroelectric-to-paraelectric phase transition at ≈518 K.

Beyond Substrates: Strain Engineering of Ferroelectric Membranes.

Strain engineering in perovskite oxides provides for dramatic control over material structure, phase, and properties, but is restricted by the discrete strain states produced by available high-quality substrates. Here, using the ferroelectric BaTiO , production of precisely strain-engineered, substrate-released nanoscale membranes is demonstrated via an epitaxial lift-off process that allows the high crystalline quality of films grown on substrates to be replicated. In turn, fine structural tuning is achieved using interlayer stress in symmetric trilayer oxide-metal/ferroelectric/oxide-metal structures fabricated from the released membranes.

Giant Superelastic Piezoelectricity in Flexible Ferroelectric BaTiO Membranes.

Mechanical displacement in commonly used piezoelectric materials is typically restricted to linear or biaxial in nature and to a few percent of the material dimensions. Here, we show that free-standing BaTiO membranes exhibit nonconventional electromechanical coupling. Under an external electric field, these superelastic membranes undergo controllable and reversible "sushi-rolling-like" 180° folding-unfolding cycles.

Enhanced lysozyme imprinting over nanoparticles functionalized with carboxyl groups for noncovalent template sorption.

Surface molecular imprinting, in particular over nanosized support materials, is very suitable for a template of bulky structure like protein. Inspired by the surface template immobilization method reported previously, we herein demonstrate an alternative strategy for enhancing specific recognition of core-shell protein-imprinted nanoparticles through prefunctionalizing the cores with noncovalent template sorption groups. For proof of this concept, silica nanoparticles chosen as the core materials were modified consecutively with 3-aminopropyltrimethoxysilane and maleic anhydride to introduce polymerizable double bonds and terminal carboxyl groups, hence capable of physically adsorbing the print protein.

Imprinting of protein over silica nanoparticles via surface graft copolymerization using low monomer concentration.

Surface imprinting and adopting a nano-sized physical form are two effective approaches to overcome the template transfer difficulty within molecularly imprinted polymers and in particular advantageous to the imprinting of macromolecular structures like proteins. The surface protein-imprinted nanoparticles based on these two strategies are attractive for biosensor development. We here demonstrate a facile way for imprinting protein over nanoparticle supports.