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Nanoindentation was performed on individual grains of a polycrystalline Mg sample with c-axis declination angles ranging from parallel (0°) to perpendicular (90°) to the c-axis. Hardness was highest at ∼0°, decreased up to ∼55°, and then increased at ∼90° to an intermediate level. At ∼0°, high-density 〈c + a〉 dislocations extended deep into the crystal, contributing to high hardness. At ∼55°, 〈c + a〉 dislocations were confined near the indent, and occasional extension twinning reoriented the crystal to ∼45°, promoting 〈a〉 slip in both matrix and twin, leading to low hardness. At ∼90°, extension twinning reoriented the crystal to ∼0°, inducing texture hardening and intermediate hardness. Despite the complex stress state in nanoindentation, which fundamentally differs from the uniaxial stress in bulk tensile and compression tests, the combined contributions of dislocation and twinning still give rise to measurable hardness anisotropy, suggesting nanoindentation as a high-throughput technique for probing orientation-dependent mechanical behavior in Mg. 

Early transition metal alkyl and hydride complexes have been widely explored for their propensity to faciltate C–H activation through a concerted σ-bond metathesis mechanism. Herein, we report the synthesis of a tris(amido) Zr(IV) alkyl complex 1 as a precursor of accessing a proposed transient Zr(IV)-hydride. Upon intramolecular C–H activation of a pendent methyl group, a strained cyclometalated complex 2 is obtained. Relief of ring strain and cooperative metal–ligand C–H activation provided access to Zr-acetylide complex 3, which is capable of undergoing insertion reactivity into carbonyl containing compounds, like aldehydes and ketones. Complexes 1–3 are characterized using multinuclear NMR spectroscopy, UV–vis spectroscopy, and X-ray crystallography. Newly reported electron-rich propargylic alcohols 6 and 7 are isolated and fully characterized using multinuclear NMR spectroscopy, ESI-MS, and FTIR. 

The indirect detection of dark matter (DM) through its annihilation products is one of the primary strategies for DM detection. One of the least constrained classes of models is neutrinophilic DM, because the annihilation products, weakly interacting neutrinos, are challenging to observe. Here, we consider a scenario where MeV-mass DM exclusively annihilates to the third neutrino mass eigenstate, which is predominantly of tau and muon flavor. In such a scenario, the potential detection rate of the neutrinos originating from the DM annihilation in our Galaxy in the conventional detectors would be suppressed by up to approximately two orders of magnitude. This is because the best sensitivity of such detectors for neutrinos with energies below approximately 100 MeV is for electron neutrino flavor. In this work, we highlight the potential of large-scale DM detectors in uncovering such signals in the tens of MeV range of DM masses. In addition, we discuss how coincident signals in direct detection DM experiments and upcoming neutrino detectors such as DUNE, Hyper-Kamiokande, and JUNO could provide new perspectives on the DM problem. Published by the American Physical Society2025 

A non-isocyanate synthetic route was used to generate 20 different ionic liquids containing either a carbamate or thiocarbamate functional group. 

Coastal jetties are commonly used throughout the world to stabilize channels and improve navigation through inlets. These engineered structures form artificial boundaries to littoral cells by reducing wave-driven longshore sediment transport across inlet entrances. Consequently, beaches adjacent to engineered inlets are subject to large gradients in longshore transport rates and are highly sensitive to changes in wave climate. Here, we quantify annual beach and nearshore sediment volume changes over a 9-yr time period along 80 km of wave- dominated coastlines in the U.S. Pacific Northwest. Beach and nearshore monitoring during the study period (2014–2023) reveal spatially coherent, multi-annual patterns of erosion and deposition on opposing sides of two engineered inlets, indicating a regional reversal of longshore-transport direction. A numerical wave model coupled with a longshore transport predictor was calibrated and validated to explore the causes for the observed spatial and temporal patterns of erosion and deposition adjacent to the inlets. The model results indicate that subtle but important changes in wave direction on seasonal to multi-annual time scales were responsible for the reversal in the net longshore sediment transport direction and opposing patterns of morphology change. Changes in longshore transport direction coincided with a reversal in the Pacific Decadal Oscillation (PDO) climate index, suggesting large-scale, multi-decadal climate variability may influence patterns of waves and sediment dynamics at other sites throughout the Pacific basin. 

We present a mechanism for producing a cosmologically significant relic density of one or more sterile neutrinos. This scheme invokes two steps: First, a population of “heavy” sterile neutrinos is created by scattering-induced decoherence of active neutrinos. Second, this population is transferred, via sterile neutrino self-interaction-mediated scatterings and decays, to one or more lighter mass ( $\sim 10\mathrm{keV}$to $\sim 1\mathrm{GeV}$) sterile neutrinos that are far more weakly (or not at all) mixed with active species and could constitute dark matter. Dark matter produced this way can evade current electromagnetic and structure-based bounds, but may nevertheless be probed by future observations. Published by the American Physical Society2024 

Genomic characterization of Cannabis sativa has accelerated rapidly in the last decade as sequencing costs have decreased and public and private interest in the species has increased. Here, we present seven new chromosome-level haplotype-phased genomes of C. sativa. All of these genotypes were alive at the time of publication, and several have numerous years of associated phenotype data. We performed a k-mer-based pangenome analysis to contextualize these assemblies within over 200 existing assemblies. This allowed us to identify unique haplotypes and genomic diversity among Cannabis sativa genotypes. We leveraged linkage maps constructed from F2 progeny of two of the assembled genotypes to characterize the recombination rate across the genome showing strong periphery-biased recombination. Lastly, we re-aligned a bulk segregant analysis dataset for the major-effect flowering locus Early1 to several of the new assemblies to evaluate the impact of reference bias on the mapping results and narrow the locus to a smaller region of the chromosome. These new assemblies, combined with the continued propagation of the genotypes, will contribute to the growing body of genomic resources for C. sativa to accelerate future research efforts. 

Amber is a molecular dynamics (MD) software package first conceived by Peter Kollman, his lab and collaborators to simulate biomolecular systems. The pmemd module is available as a serial version for central processing units (CPUs), NVIDIA and Advanced Micro Devices (AMD) graphics processing unit (GPU) versions as well as Message Passing Interface (MPI) parallel versions. Advanced capabilities include thermodynamic integration, replica exchange MD and accelerated MD methods. A brief update to the software and recently added capabilities is described in this Application Note.