A dislocation-density based crystalline plasticity (DCP) and nonlinear finite element (FE) analysis were used to predict, and fundamentally understand how and why fracture nucleation and propagation are related to the interrelated microstructural mechanisms of dislocation-density pileups, GB structure, orientation, and total and partial dislocation density interactions within and adjacent for a random low angle grain boundary (LAGB) and a random high angle GB (HAGB). The GB orientations and structures were obtained from micropillar experiments, such that LAGBs and the HAGBs can be accurately represented and used for the modeling predictions. The normal stress, density of pileups, and dislocation-density accumulation along and within the GB were higher for the low angle GB bicrystal.
View Article and Find Full Text PDFWe introduce mvSuSiE, a multi-trait fine-mapping method for identifying putative causal variants from genetic association data (individual-level or summary data). mvSuSiE learns patterns of shared genetic effects from data, and exploits these patterns to improve power to identify causal SNPs. Comparisons on simulated data show that mvSuSiE is competitive in speed, power and precision with existing multi-trait methods, and uniformly improves on single-trait fine-mapping (SuSiE) in each trait separately.
View Article and Find Full Text PDFChunks are multiword sequences with independent meaning and function, or formulaic based on the intuition of native speakers, hypothesized to be holistically restored and retrieved in the mental lexicon. Previous studies suggest that pauses and intonational boundaries tend to occur at the boundaries of chunks, but less discussion was made on the influence of chunk categories over mental processing and on pause placement associated with intonational continuity. This study adopted spontaneous monologs of Mandarin natives in formal and informal settings.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
February 2023
Type II and IV twins with irrational twin boundaries are studied by high-resolution transmission electron microscopy in two plagioclase crystals. The twin boundaries in these and in NiTi are found to relax to form rational facets separated by disconnections. The topological model (TM), amending the classical model, is required for a precise theoretical prediction of the orientation of the Type II/IV twin plane.
View Article and Find Full Text PDFEnhancing electron correlation in a weakly interacting topological system has great potential to promote correlated topological states of matter with extraordinary quantum properties. Here, the enhancement of electron correlation in a prototypical topological metal, namely iridium dioxide (IrO ), via doping with 3d transition metal vanadium is demonstrated. Single-crystalline vanadium-doped IrO nanowires are synthesized through chemical vapor deposition where the nanowire yield and morphology are improved by creating rough surfaces on substrates.
View Article and Find Full Text PDFSmall disks are often the specimen of choice for exposure in nuclear reactor environments, and this geometry invariably limits the types of mechanical testing that can be performed on the specimen. Recently, shear punch testing has been utilized to evaluate changes arising from neutron irradiation in test reactor environments on these small disk specimens. As part of a broader effort to link accelerated testing using ion irradiation and conventional neutron irradiation techniques, a novel microshear specimen geometry was developed for use with heavy-ion irradiated specimens.
View Article and Find Full Text PDFThe emergence of van der Waals (vdW) magnets has created unprecedented opportunities to manipulate magnetism for advanced spintronics based upon all-vdW heterostructures. Among various vdW magnets, CrTe possesses high temperature ferromagnetism along with possible topological spin textures. As this system can support self-intercalation in the vdW gap, it is crucial to precisely pinpoint the exact intercalation to understand the intrinsic magnetism of the system.
View Article and Find Full Text PDFRecent experimental studies show that co-sputtering solutes with Al, together, can refine columnar grain size around few tens of nanometers and promote the formation and enhance the stability of planar defects such as stacking faults (SFs) and grain boundaries (GBs) in Al alloys. These crystal defects and fine columnar grains result in high strength, enhanced strain hardening and thermal stability of Al alloys. Using first-principles density-functional theory (DFT) calculations, we studied the role of eleven solutes in tailoring kinetics and energetics of adatoms and clusters on Al {111} surface, stable and unstable stacking fault energies, and kinetic energy barriers for the migration of defects.
View Article and Find Full Text PDFThe discovery of atomically thin van der Waals magnets (.., CrI and CrGeTe) has triggered a renaissance in the study of two-dimensional (2D) magnetism.
View Article and Find Full Text PDFBackground: Sequence logo plots have become a standard graphical tool for visualizing sequence motifs in DNA, RNA or protein sequences. However standard logo plots primarily highlight enrichment of symbols, and may fail to highlight interesting depletions. Current alternatives that try to highlight depletion often produce visually cluttered logos.
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