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The terrestrial carbon cycle varies dynamically on hourly to weekly scales, making it difficult to observe. Geostationary (“weather”) satellites like the Geostationary Environmental Operational Satellite - R Series (GOES-R) deliver near-hemispheric imagery at a ten-minute cadence. The Advanced Baseline Imager (ABI) aboard GOES-R measures visible and near-infrared spectral bands that can be used to estimate land surface properties and carbon dioxide flux. However, GOES-R data are designed for real-time dissemination and are difficult to link with eddy covariance time series of land-atmosphere carbon dioxide exchange. We compiled three-year time series of GOES-R land surface attributes including visible and near-infrared reflectances, land surface temperature (LST), and downwelling shortwave radiation (DSR) at 314 ABI fixed grid pixels containing eddy covariance towers. We demonstrate how to best combine satellite andin-situdatasets and show how ABI attributes useful for ecosystem monitoring vary across space and time. By connecting observation networks that infer rapid changes to the carbon cycle, we can gain a richer understanding of the processes that control it.

 

Doping, or incremental substitution of one element for another, is an effective way to tailor a compound’s structure as well as its physical and chemical properties. Herein, we replaced up to 30% of Ni with Co in members of the family of layered LiNiB compounds, stabilizing the high-temperature polymorph of LiNiB while the room-temperature polymorph does not form. By studying this layered boride with in situ high-temperature powder diffraction, we obtained a distorted variant of LiNi0.7Co0.3B featuring a perfect interlayer placement of [Ni0.7Co0.3B] layers on top of each other─a structural motif not seen before in other borides. Because of the Co doping, LiNi0.7Co0.3B can undergo a nearly complete topochemical Li deintercalation under ambient conditions, resulting in a metastable boride with the formula Li0.04Ni0.7Co0.3B. Heating of Li0.04Ni0.7Co0.3B in anaerobic conditions led to yet another metastable boride, Li0.01Ni0.7Co0.3B, with a CoB-type crystal structure that cannot be obtained by simple annealing of Ni, Co, and B. No significant alterations of magnetic properties were detected upon Co-doping in the temperature-independent paramagnet LiNi0.7Co0.3B or its Li-deintercalated counterparts. Finally, Li0.01Ni0.7Co0.3B stands out as an exceptional catalyst for the selective hydrogenation of the vinyl C═C bond in 3-nitrostyrene, even in the presence of other competing functional groups. This research showcases an innovative approach to heterogeneous catalyst design by meticulously synthesizing metastable compounds. 

The current system of peer review drives racial and gender disparities in publication and funding outcomes and can suppress the perspectives of marginalized scholars. Established researchers have an opportunity to help to build a fairer and more inclusive peer review culture by advocating for and empowering their trainees. 

We present a comprehensive study of the inhomogeneous mixed-valence compound, EuPd₃S₄, by electrical transport, X-ray diffraction, time-domain¹⁵¹Eu synchrotron Mössbauer spectroscopy, and X-ray absorption spectroscopy measurements under high pressure. Electrical transport measurements show that the antiferromagnetic ordering temperature,T_N, increases rapidly from 2.8 K at ambient pressure to 23.5 K at ~19 GPa and plateaus between ~19 and ~29 GPa after which no anomaly associated withT_Nis detected. A pressure-induced first-order structural transition from cubic to tetragonal is observed, with a rather broad coexistence region (~20 GPa to ~30 GPa) that corresponds to theT_Nplateau. Mössbauer spectroscopy measurements show a clear valence transition from approximately 50:50 Eu²⁺:Eu³⁺to fully Eu³⁺at ~28 GPa, consistent with the vanishing of the magnetic order at the same pressure. X-ray absorption data show a transition to a fully trivalent state at a similar pressure. Our results show that pressure first greatly enhancesT_N, most likely via enhanced hybridization between the Eu 4fstates and the conduction band, and then, second, causes a structural phase transition that coincides with the conversion of the europium to a fully trivalent state.

 

Yield gaps, here defined as the difference between actual and attainable yields, provide a framework for assessing opportunities to increase agricultural productivity. Previous global assessments, centred on a single year, were unable to identify temporal variation. Here we provide a spatially and temporally comprehensive analysis of yield gaps for ten major crops from 1975 to 2010. Yield gaps have widened steadily over most areas for the eight annual crops and remained static for sugar cane and oil palm. We developed a three-category typology to differentiate regions of ‘steady growth’ in actual and attainable yields, ‘stalled floor’ where yield is stagnated and ‘ceiling pressure’ where yield gaps are closing. Over 60% of maize area is experiencing ‘steady growth’, in contrast to ∼12% for rice. Rice and wheat have 84% and 56% of area, respectively, experiencing ‘ceiling pressure’. We show that ‘ceiling pressure’ correlates with subsequent yield stagnation, signalling risks for multiple countries currently realizing gains from yield growth.

 

The astrophysical environments capable of triggering heavy-element synthesis via rapid neutron capture (ther-process) remain uncertain. While binary neutron star mergers (NSMs) are known to forger-process elements, certain rare supernovae (SNe) have been theorized to supplement—or even dominate—r-production by NSMs. However, the most direct evidence for such SNe, unusual reddening of the emission caused by the high opacities ofr-process elements, has not been observed. Recent work identified the distribution ofr-process material within the SN ejecta as a key predictor of the ease with which signals associated withr-process enrichment could be discerned. Though this distribution results from hydrodynamic processes at play during the SN explosion, thus far it has been treated only in a parameterized way. We use hydrodynamic simulations to model how disk winds—the alleged locus ofr-production in rare SNe—mix with initiallyr-process-free ejecta. We study mixing as a function of the wind mass, wind duration, and the initial SN explosion energy, and find that it increases with the first two of these and decreases with the third. This suggests that SNe accompanying the longest long-duration gamma-ray bursts are promising places to search for signs ofr-process enrichment. We use semianalytic radiation transport to connect hydrodynamics to electromagnetic observables, allowing us to assess the mixing level at which the presence ofr-process material can be diagnosed from SN light curves. Analytic arguments constructed atop this foundation imply that a wind-drivenr-process-enriched SN model is unlikely to explain standard energetic SNe.

 

The National Research Council’s Framework for K-12 Science Education and the subsequent Next Generation Science Standards have provided a widespread common language for science education reform over the last decade. These efforts have naturally been targeted at the K-12 levels, but we have argued that the three dimensions outlined in these documents—scientific practices, disciplinary core ideas, and crosscutting concepts (together termed three-dimensional learning)—are also a productive route for reform in college-level science courses. However, how and why college-level faculty might be motivated to incorporate three-dimensional learning into their courses is not well understood. Here, we report a mixed-methods study of participants in an interdisciplinary professional development program designed to support faculty in developing assessments and instruction aligned with three-dimensional learning. One cohort of faculty (N = 8) was interviewed, and four cohorts of faculty (N = 33) were surveyed. Using expectancy-value theory as an organizational framework, we identified themes of perceived values and costs that participants discussed in implementing three-dimensional learning. Based on a cluster analysis of all survey participants’ motivational profiles, we propose that these themes apply to the broader population of participants in this program. We recommend specific interventions to improve faculty motivation for implementing three-dimensional learning: emphasizing the utility value of three-dimensional learning in effecting positive learning gains for students; drawing connections between the dimensions of three-dimensional learning and faculty’s disciplinary identities; highlighting scientific practices as a key leverage point for faculty ability beliefs; minimizing cognitive dissonance for faculty in understanding the similarities and differences between the three dimensions; focusing on assessment writing as a keystone professional development activity; and aligning local evaluation practices and promotion policies with the 3DL framework.

 

Gnathia jimmybuffettisp. nov. is described from the Florida Keys. Morphological characterization of the male, female, and juvenile as well as the life cycle development of the female is examined. The male of this new species is distinguished from other species from the Tropical Northwestern Atlantic marine province by the slightly produced frontal margin; absent mediofrontal process; single, strong, conical superior frontolateral process, with 2 pairs of long simple setae; and rounded inferior frontolateral process, the weak distally curved mandible with weakly convex dentate blade. In addition, molecular characterization for three life stages, (males, females, and praniza), is provided, as well as evidence for linking host DNA to juvenile stages. This paper contributes to our understanding of the gnathiid biodiversity of the Tropical Atlantic realm, specifically the Floridian ecoregion. Furthermore, this paper validates the methods of extracting and identifying host DNA from the gnathiid blood meal.