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  1. e present a sample of 305 QSO candidates having |b| < 30◦, the majority with GALEX magnitudes NUV < 18.75. To generate this sample, we apply UV-IR color selection criteria to photometric data from the Ultraviolet GAlactic Plane Survey (UVGAPS) as part of GALEX-CAUSE, the Million Quasars Catalog, Gaia DR2, and Pan-STARRS DR1. 165 of these 305 candidate UV-bright AGN (54%) have published spectroscopic redshifts from 45 different surveys, confirming them as AGN. We further obtained low-dispersion, optical, longslit spectra with the APO 3.5-m, MDM 2.4-m, and MDM 1.3-m telescopes for 84 of the candidates, and confirm 86% (N = 72) as AGN, generally with z < 0.6. These sources fill a gap in the Galactic latitude coverage of the available samples of known UV-bright QSO background probes. Along with a description of the confirmed QSO properties, we provide the fully-reduced, flux and wavelength-calibrated spectra of 84 low-latitude QSOs through the Mikulski Archive for Space Telescopes. Future HST/COS spectroscopy of these low-Galactic-latitude QSOs has the potential to transform our view of the Milky Way and Local Group circumgalactic medium. 
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    Free, publicly-accessible full text available March 18, 2025
  2. The formation of isothermal ω phase precipitates and its influence on subsequent fine-scale α precipitation is investigated in a metastable β-titanium alloy, Ti-10V-2Fe-3Al. Atom-probe tomography and high-resolution transmission electron microscopy reveal that the rejection of Al, a potent α stabilizer, from the growing isothermal ω precipitates at 330°C, aids in the formation of α precipitates. Additionally, the presence of α/ω and α/β interfaces conclusively establish that these α precipitates form at the β/ω interface. Interestingly, the local Al pile-up at this interface results in a substantially higher than equilibrium Al content within the α precipitates at the early stages of formation. This can be rationalized based on a novel three-phase β+ω+α metastable equilibrium at a lower annealing temperature (330°C, below the ω solvus). Subsequent annealing at a higher temperature (600°C, above the ω solvus), dissolves the ω precipitates and re-establishes the two-phase β+α equilibrium in concurrence with solution thermodynamic predictions. 
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    Free, publicly-accessible full text available September 1, 2024
  3. Free, publicly-accessible full text available September 1, 2024
  4. A finite horizon nonlinear optimal control problem is considered for which the associated Hamiltonian satisfies a uniform semiconcavity property with respect to its state and costate variables. It is shown that the value function for this optimal control problem is equivalent to the value of a min-max game, provided the time horizon considered is sufficiently short. This further reduces to maximization of a linear functional over a convex set. It is further proposed that the min-max game can be relaxed to a type of stat (stationary) game, in which no time horizon constraint is involved. 
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  5. Abstract Protein posttranslational modification (PTM) is a biochemical mechanism benefitting cellular adaptation to dynamic intracellular and environmental conditions. Recently, several acylation marks have been identified as new protein PTMs occurring on specific lysine residues in mammalian cells: isobutyrylation, methacrylation, benzoylation, isonicotinylation, and lactylation. These acylation marks were initially discovered to occur on nucleosomal histones, but they potentially occur as prevalent biomarkers on non‐histone proteins as well. The existence of these PTMs is a downstream consequence of metabolism and demonstrates the intimate crosstalk between active cellular metabolites and regulation of protein function. Emerging evidence indicates that these acylation marks on histones affect DNA transcription and are functionally distinct from the well‐studied lysine acetylation. Herein, we discuss enzymatic regulation and metabolic etiology of these acylations, 'reader' proteins that recognize different acylations, and their possible physiological and pathological functions. Several of these modifications correlate with other well‐studied acylations and fine‐tune the regulation of gene expression. Overall, findings of these acylation marks reveal new molecular links between metabolism and epigenetics and open up many questions for future investigation. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. 
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  6. Kirigami metamaterials dramatically change their shape through a coordinated motion of nearly rigid panels and flexible slits. Here, we study a model system for mechanism-based planar kirigami featuring periodic patterns of quadrilateral panels and rhombi slits, with the goal of predicting their engineering scale response to a broad range of loads. We develop a generalized continuum model based on the kirigami’s effective (cell-averaged) nonlinear deformation, along with its slit actuation and gradients thereof. The model accounts for three sources of elasticity: a strong preference for the effective fields to match those of a local mechanism, inter-panel stresses arising from gradients in slit actuation, and distributed hinge bending. We provide a finite-element formulation of this model and implement it using the commercial software Abaqus. Simulations of the model agree quantitatively with experiments across designs and loading conditions. 
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