Asymmetric spin-wave dispersion due to Dzyaloshinskii-Moriya interaction in an ultrathin Pt/CoFeB film

Employing Brillouin spectroscopy, strong interfacial Dzyaloshinskii-Moriya interactions have been observed in an ultrathin Pt/CoFeB film. Our micromagnetic simulations show that spin-wave nonreciprocity due to asymmetric surface pinning is insignificant for the 0.8nmthick CoFeB film studied. The observed high asymmetry of the monotonic spin wave dispersion relation is thus ascribed to strong Dzyaloshinskii-Moriya interactions present at the Pt/CoFeB interface. Our findings should further enhance the significance of CoFeB as an important material for magnonic, spintronic and skyrmionic applications.Comment: 12 pages, 4 figure

Structural Insight into Layer Gliding and Lattice Distortion in Layered Manganese Oxide Electrodes for Potassium-Ion Batteries

Potassium-ion batteries (PIBs) are an emerging, affordable, and environmentally friendly alternative to lithium-ion batteries, with their further development driven by the need for suitably performing electrode materials capable of reversibly accommodating the relatively large K+. Layer-structured manganese oxides are attractive as electrodes for PIBs, but suffer from structural instability and sluggish kinetics of K+ insertion/extraction, leading to poor rate capability. Herein, cobalt is successfully introduced at the manganese site in the KxMnO2 layered oxide electrode material and it is shown that with only 5% Co, the reversible capacity increases by 30% at 22 mA g-1 and by 92% at 440 mA g-1. In operando synchrotron X-ray diffraction reveals that Co suppresses Jahn-Teller distortion, leading to more isotropic migration pathways for K+ in the interlayer, thus enhancing the ionic diffusion and consequently, rate capability. The detailed analysis reveals that additional phase transitions and larger volume change occur in the Co-doped material as a result of layer gliding, with these associated with faster capacity decay, despite the overall capacity remaining higher than the pristine material, even after 500 cycles. These results assert the importance of understanding the detailed structural evolution that underpins performance that will inform the strategic design of electrode materials for high-performance PIBs

Direct observation of the Dzyaloshinskii-Moriya interaction in a Pt/Co/Ni film

The interfacial Dzyaloshinskii-Moriya interaction (DMI) in an in-plane anisotropic Pt(4nm)/Co(1.6nm)/Ni(1.6nm) film has been directly observed by Brillouin spectroscopy. It is manifested in the asymmetry of the measured magnon dispersion relation, from which the DMI constant has been evaluated. Linewidth measurements reveal that the lifetime of the magnons is asymmetric with respect to their counter-propagating directions. The lifetime asymmetry is dependent on the magnon frequency, being more pronounced the higher the frequency. Analytical calculations of the magnon dispersion relation and linewidth agree well with experiments.Comment: 15 pages, 4 figure

Human Urinary Epithelial Cells as a Source of Engraftable Hepatocyte-Like Cells Using Stem Cell Technology

K

Multiple telecouplings and their complex interrelationships

Increasingly, the world is becoming socioeconomically and environmentally connected, but many studies have focused on human-environment interactions within a particular area. Although some studies have considered the impacts of external factors, there is little research on multiple reciprocal socioeconomic and environmental interactions between a focal area and other areas. Here we address this important kowledge gap by applying the new integrated framework of telecouplings (socioeconomic and environmental interactions between two or more areas over distances). Results show that even a protected area - i.e., the Wolong Nature Reserve for giant pandas in southwest China - has multiple telecoupling processes with the rest of the world; these include panda loans, tourism, information dissemination, conservation subsidies, and trade of aricultural and industrial products. The telecoupling processes exhibit nonlinear patterns, they change over time, and they have varying socioeconomic and environmental effects across the world. We also find complex relationships among different telecouplings - e.g., amplification, offsetting, spatial overlaps - which cannot be detected by traditional separate studies. Such an integrated study leads to a more comprehensive understanding of distant human-enviroment interactions and has significant implications for global sustainability and human well-being

Genomic Profiling of Childhood Tumor Patient-Derived Xenograft Models to Enable Rational Clinical Trial Design.

Accelerating cures for children with cancer remains an immediate challenge as a result of extensive oncogenic heterogeneity between and within histologies, distinct molecular mechanisms evolving between diagnosis and relapsed disease, and limited therapeutic options. To systematically prioritize and rationally test novel agents in preclinical murine models, researchers within the Pediatric Preclinical Testing Consortium are continuously developing patient-derived xenografts (PDXs)-many of which are refractory to current standard-of-care treatments-from high-risk childhood cancers. Here, we genomically characterize 261 PDX models from 37 unique pediatric cancers; demonstrate faithful recapitulation of histologies and subtypes; and refine our understanding of relapsed disease. In addition, we use expression signatures to classify tumors for TP53 and NF1 pathway inactivation. We anticipate that these data will serve as a resource for pediatric oncology drug development and will guide rational clinical trial design for children with cancer

Stochastic analysis of three-dimensional hydraulic conductivity upscaling in a heterogeneous tropical soil

[EN] Hydraulic conductivity (K) heterogeneity is seldom considered in geotechnical practice for the impossibility of sampling the entire area of interest and for the difficulty of accounting for scale effects. Stochastic three-dimensional K upscaling can tackle these two problems, and a workflow is described with an application in a tropical soil. The application shows that K heterogeneity can be incorporated in the daily practice of the geotechnical modeler while discussing the aspects to consider when performing the upscaling so that the upscaled models reproduce the average fluxes at the fine scale.The authors thank the financial support by the Brazilian National Council for Scientific and Technological Development (CNPq) (Project 401441/2014-8). The doctoral fellowship award to the first author by the Coordination of Improvement of Higher Level Personnel (CAPES) is gratefully acknowledged. The first author thanks the International Mobility Grant awarded by CNPq (200597/2015-9) and Santander mobility. The authors also thank DHI-WASI for providing a FEFLOW Software license.Almeida De-Godoy, V.; Zuquette, L.; Gómez-Hernández, JJ. (2018). Stochastic analysis of three-dimensional hydraulic conductivity upscaling in a heterogeneous tropical soil. Computers and Geotechnics. 100:174-187. https://doi.org/10.1016/j.compgeo.2018.03.004S17418710