Mapping Polar Distortions using Nanobeam Electron Diffraction and a Cepstral Approach.

Measuring local polar ordering is key to understanding ferroelectricity in thin films, especially for systems with small domains or significant disorder. Scanning nanobeam electron diffraction (NBED) provides an effective local probe of lattice parameters, local fields, polarization directions, and charge densities, which can be analyzed using a relatively low beam dose over large fields of view. However, quantitatively extracting the magnitudes and directions of polarization vectors from NBED remains challenging.

Dimensionality-Induced Change in Topological Order in Multiferroic Oxide Superlattices.

We construct ferroelectric (LuFeO_{3})_{m}/(LuFe_{2}O_{4}) superlattices with varying index m to study the effect of confinement on topological defects. We observe a thickness-dependent transition from neutral to charged domain walls and the emergence of fractional vortices. In thin LuFeO_{3} layers, the volume fraction of domain walls grows, lowering the symmetry from P6_{3}cm to P3c1 before reaching the nonpolar P6_{3}/mmc state, analogous to the group-subgroup sequence observed at the high-temperature ferroelectric to paraelectric transition.

Nivolumab-associated Stevens-Johnson syndrome in a patient with lung cancer.

Nivolumab is a fully human immunoglobulin G4 immune checkpoint inhibitor antibody approved for use in the treatment of several malignancies such as lung cancer. Cutaneous reactions to checkpoint inhibitors are frequent, appearing in approximately 40% of patients. Although most of the reactions are well tolerated, these drugs can lead to severe cutaneous adverse reactions, but a quick recognition of the symptoms can significantly decrease their mortality.

The exit-wave power-cepstrum transform for scanning nanobeam electron diffraction: robust strain mapping at subnanometer resolution and subpicometer precision.

Scanning nanobeam electron diffraction (NBED) with fast pixelated detectors is a valuable technique for rapid, spatially resolved mapping of lattice structure over a wide range of length scales. However, intensity variations caused by dynamical diffraction and sample mistilts can hinder the measurement of diffracted disk centers as necessary for quantification. Robust data processing techniques are needed to provide accurate and precise measurements for complex samples and non-ideal conditions.

Vitiligo-like lesions located over In-transit metastases of malignant melanoma as a clinical marker of complete response to pembrolizumab.

Anti-programmed cell death (PD)-1 therapies in metastatic tumors have a high incidence of immune adverse events, including cutaneous manifestations such as vitiligo-like lesions. This side effect is associated with increased survival and it is a clinical marker of response to treatment. This case report is a graphic representation of the appearance of vitiligo-like lesions over in-transit metastases of malignant melanoma linked to a complete response to treatment with pembrolizumab.

Ultrahigh Rate Performance of a Robust Lithium Nickel Manganese Cobalt Oxide Cathode with Preferentially Orientated Li-Diffusing Channels.

Lithium nickel manganese cobalt oxide (NMC) materials, with low cost and high energy density, are considered to be among the most promising cathode materials for Li-ion batteries (LIBs). However, several issues have hindered their further deployment, particularly for high-powered applications, including limited rate capability, capacity loss during cycling (especially at high temperatures and high voltages), and difficulty in reproducibly preparing the desired particle morphology. In this work, we have developed a robust LiNiMnCoO cathode material (NMC-111) capable of high-rate performance for LIBs.

Highly conductive and chemically stable alkaline anion exchange membranes via ROMP of -cyclooctene derivatives.

Alkaline anion exchange membranes (AAEMs) are an important component of alkaline exchange membrane fuel cells (AEMFCs), which facilitate the efficient conversion of fuels to electricity using nonplatinum electrode catalysts. However, low hydroxide conductivity and poor long-term alkaline stability of AAEMs are the major limitations for the widespread application of AEMFCs. In this paper, we report the synthesis of highly conductive and chemically stable AAEMs from the living polymerization of -cyclooctenes.

Revealing the atomic ordering of binary intermetallics using in situ heating techniques at multilength scales.

Ordered intermetallic nanoparticles are promising electrocatalysts with enhanced activity and durability for the oxygen-reduction reaction (ORR) in proton-exchange membrane fuel cells (PEMFCs). The ordered phase is generally identified based on the existence of superlattice ordering peaks in powder X-ray diffraction (PXRD). However, after employing a widely used postsynthesis annealing treatment, we have found that claims of "ordered" catalysts were possibly/likely mixed phases of ordered intermetallics and disordered solid solutions.

Pt-Rich/Sn-Rich/Pt Nanocubes As Highly Active and Stable Electrocatalysts for the Ethanol Oxidation Reaction.

Direct ethanol fuel cells are one of the most promising electrochemical energy conversion devices for portable, mobile and stationary power applications. However, more efficient and stable and less expensive electrocatalysts are still required. Interestingly, the electrochemical performance of the electrocatalysts toward the ethanol oxidation reaction can be remarkably enhanced by exploiting the benefits of structural and compositional sensitivity and control.

Sampling limits for electron tomography with sparsity-exploiting reconstructions.

Electron tomography (ET) has become a standard technique for 3D characterization of materials at the nano-scale. Traditional reconstruction algorithms such as weighted back projection suffer from disruptive artifacts with insufficient projections. Popularized by compressed sensing, sparsity-exploiting algorithms have been applied to experimental ET data and show promise for improving reconstruction quality or reducing the total beam dose applied to a specimen.

A Simple Preparation Method for Full-Range Electron Tomography of Nanoparticles and Fine Powders.

Electron tomography has become a valuable and widely used tool for studying the three-dimensional nanostructure of materials and biological specimens. However, the incomplete tilt range provided by conventional sample holders limits the fidelity and quantitative interpretability of tomographic images by leaving a "missing wedge" of unknown information in Fourier space. Imaging over a complete range of angles eliminates missing wedge artifacts and dramatically improves tomogram quality.

Tuning the Electrocatalytic Oxygen Reduction Reaction Activity and Stability of Shape-Controlled Pt-Ni Nanoparticles by Thermal Annealing - Elucidating the Surface Atomic Structural and Compositional Changes.

Shape-controlled octahedral Pt-Ni alloy nanoparticles exhibit remarkably high activities for the electroreduction of molecular oxygen (oxygen reduction reaction, ORR), which makes them fuel-cell cathode catalysts with exceptional potential. To unfold their full and optimized catalytic activity and stability, however, the nano-octahedra require post-synthesis thermal treatments, which alter the surface atomic structure and composition of the crystal facets. Here, we address and strive to elucidate the underlying surface chemical processes using a combination of ex situ analytical techniques with in situ transmission electron microscopy (TEM), in situ X-ray diffraction (XRD), and in situ electrochemical Fourier transformed infrared (FTIR) experiments.

Atomically engineered ferroic layers yield a room-temperature magnetoelectric multiferroic.

Materials that exhibit simultaneous order in their electric and magnetic ground states hold promise for use in next-generation memory devices in which electric fields control magnetism. Such materials are exceedingly rare, however, owing to competing requirements for displacive ferroelectricity and magnetism. Despite the recent identification of several new multiferroic materials and magnetoelectric coupling mechanisms, known single-phase multiferroics remain limited by antiferromagnetic or weak ferromagnetic alignments, by a lack of coupling between the order parameters, or by having properties that emerge only well below room temperature, precluding device applications.

[Apocrine hidrocystoma associated with gouty tophi of the pinna].

Background: Apocrine hidrocystomas, also known as apocrine cystadenomas, are bening cystic tumours derived from the secretory portion of apocrine sweat glands.

Clinical Case: A 78-year old female was referred to our division for assesment an asymptomatic translucent, well-defined cystic lesion located on the upper helix. The histological features were consistent with apocrine hidrocystoma coexisting with gouty tophi.

Pinning Susceptibility: The Effect of Dilute, Quenched Disorder on Jamming.

We study the effect of dilute pinning on the jamming transition. Pinning reduces the average contact number needed to jam unpinned particles and shifts the jamming threshold to lower densities, leading to a pinning susceptibility, χ_{p}. Our main results are that this susceptibility obeys scaling form and diverges in the thermodynamic limit as χ_{p}∝|ϕ-ϕ_{c}^{∞}|^{-γ_{p}} where ϕ_{c}^{∞} is the jamming threshold in the absence of pins.

Nanomaterial datasets to advance tomography in scanning transmission electron microscopy.

Electron tomography in materials science has flourished with the demand to characterize nanoscale materials in three dimensions (3D). Access to experimental data is vital for developing and validating reconstruction methods that improve resolution and reduce radiation dose requirements. This work presents five high-quality scanning transmission electron microscope (STEM) tomography datasets in order to address the critical need for open access data in this field.

Multicomponent Nanomaterials with Complex Networked Architectures from Orthogonal Degradation and Binary Metal Backfilling in ABC Triblock Terpolymers.

Selective degradation of block copolymer templates and backfilling the open mesopores is an effective strategy for the synthesis of nanostructured hybrid and inorganic materials. Incorporation of more than one type of inorganic material in orthogonal ways enables the synthesis of multicomponent nanomaterials with complex yet well-controlled architectures; however, developments in this field have been limited by the availability of appropriate orthogonally degradable block copolymers for use as templates. We report the synthesis and self-assembly into cocontinuous network structures of polyisoprene-block-polystyrene-block-poly(propylene carbonate) where the polyisoprene and poly(propylene carbonate) blocks can be orthogonally removed from the polymer film.