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Abstract KMT-2018-BLG-0029Lb and OGLE-2019-BLG-0960Lb were the lowest mass-ratio microlensing planets at the time of discovery. For both events, microlensing parallax measurements from the Spitzer Space Telescope implied lens systems that were more distant and massive than those inferred from the ground-based parallax. Here, we report on the detection of excess flux aligned to the event locations using Keck Adaptive Optics imaging, which is consistent with the expected brightness of main-sequence hosts under the ground-based parallax, but inconsistent with that predicted by Spitzer. Based on the excess flux, ground-based parallax, and angular Einstein radius, we determine KMT-2018-BLG-0029Lb to be a 4.2 ± 0.5M_⊕planet orbiting a 0.70 ± 0.07M_⊙host at a projected separation of 3.1 ± 0.3 au, and OGLE-2019-BLG-0960Lb to be a 2.0 ± 0.2M_⊕planet orbiting a 0.40 ± 0.03M_⊙host at a projected separation of 1.7 ± 0.1 au. We report on additional light-curve models for KMT-2018-BLG-0029 under the generalized inner-outer (offset) degeneracy, which were not reported in the original analysis. We point out inconsistencies in the inner/outer labeling of the degenerate models in the lens and source planes, and advocate for the lens-plane convention, which refers to the planet being closer or further to the host star compared to the image it perturbs. Lastly, we discuss the possibility of breaking this degeneracy via ground concurrent observations with the Roman Space Telescope. 

Abstract The brain can be decomposed into large-scale functional networks, but the specific spatial topographies of these networks and the names used to describe them vary across studies. Such discordance has hampered interpretation and convergence of research findings across the field. We have developed theNetwork Correspondence Toolbox(NCT) to permit researchers to examine and report spatial correspondence between their novel neuroimaging results and multiple widely used functional brain atlases. We provide several exemplar demonstrations to illustrate how researchers can use the NCT to report their own findings. The NCT provides a convenient means for computing Dice coefficients with spin test permutations to determine the magnitude and statistical significance of correspondence among user-defined maps and existing atlas labels. The adoption of the NCT will make it easier for network neuroscience researchers to report their findings in a standardized manner, thus aiding reproducibility and facilitating comparisons between studies to produce interdisciplinary insights. 

N-Heterocyclic carbene-carbodiimide (NHC-CDI) adducts are versatile compounds that can be used as ligands and (pre)catalysts, but their systematic structure–property relationships are underexplored. Herein, we investigated how structural electronic variations on both the NHC and CDI affect the inherent kinetic and thermodynamic properties of the adducts. Using in situ carbene trapping and variable-temperature NMR spectroscopy, we measured the rates of dissociation and the equilibrium constants and then used Eyring and van’t Hoff analyses to calculate ΔG‡ and ΔG, respectively. Linear free-energy relationships indicate that changing the para position of the CDI substituents yields a similar effect to changing the NHC core. These CDI structural modifications affected the adducts’ thermodynamics (ΔG) more than the kinetics (ΔG‡) and were found to be influenced more by inductive, rather than resonance, factors. Preliminary results suggest a steric threshold beyond which steric effects dominate electronic effects in governing the strength of the adduct bond. This systematic investigation provides valuable insight into the design of NHC-CDIs for current and future applications. 

Abstract. Predictions of future sea-level change and ice-sheet stability rely on accurate reconstructions of sea levels for past warm intervals, such as the mid-Pliocene Warm Period (MPWP; 3.264–3.025 Ma). The magnitude of MPWP glacial cycles and the relative contribution of meltwater sources remain uncertain. We explore this issue by modeling processes of glacial isostatic adjustment for a wide range of possible MPWP ice-sheet melt zones, including North America, Greenland, Eurasia, and West Antarctica, as well as the Wilkes Basin, the Aurora Basin, and the embayment of Prydz Bay in East Antarctica. As a case study, we use a series of ice histories together with a suite of viscoelastic Earth models to predict global changes in sea level from the Marine Isotope Stage (MIS) M2 glacial to the MIS KM3 interglacial. At the Whanganui Basin (New Zealand), a location with stratigraphic constraints on Pliocene glacial–interglacial sea-level amplitude, the calculated local-sea-level (LSL) rise is on average ∼ 15 % lower than the associated change in the global mean sea level (GMSL) in the ice-sheet scenarios explored here. In contrast, the calculated LSL rise over the deglaciation from MIS M2 to MIS KM3 at Enewetak Atoll is systematically larger than the GMSL change by 10 %. While no single LSL observation (field site) can provide a unique constraint on the sources of ice melt observed during this period, combinations of observations have the potential to yield a stronger constraint on GMSL change and to narrow the list of possible sources.