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Abstract The Institutional Grammar (IG) is a rigorous tool for analyzing the laws and policies governing nonprofit organizations; however, its use was limited due to the time-consuming nature of hand-coding. We introduce an advance in Natural Language Processing using a semantic role labeling (SRL) classifier that reliably codes rules governing and guiding nonprofit organizations. This paper provides guidance for how to hand-code using the IG, preprocess text for machine learning, and demonstrates the SRL classifier for automated IG coding. We then compare the hand-coding to the SRL coding to demonstrate its accuracy. The advances in machine learning now make it feasible to utilize the IG for nonprofit research questions focused on inter-organizational collaborations, government contracts, federated nonprofit organizational compliance, and nonprofit governance, among others. An added benefit is that the IG is adaptable for different languages, thus enabling cross-national comparative research. By providing examples throughout the paper, we demonstrate how to use the IG and the SRL classifier to address research questions of interest to nonprofit scholars. 

Abstract Synthetic ensemble forecasts are an important tool for testing the robustness of forecast‐informed reservoir operations (FIRO). These forecasts are statistically generated to mimic the skill of hindcasts derived from operational ensemble forecasting systems, but they can be created for time periods when hindcast data are unavailable, allowing for a more comprehensive evaluation of FIRO policies. Nevertheless, it remains unclear how to determine whether a candidate synthetic ensemble forecasting approach is sufficiently representative of its real‐world counterpart to support FIRO policy evaluation. This highlights a need for formalfit‐for‐purposevalidation frameworks to advance synthetic forecasting as a generalizable risk analysis strategy. We address this research gap by first introducing a novel operations‐based validation framework, where reservoir storage and release simulations under a FIRO policy are compared when forced with a single ensemble hindcast and many different synthetic ensembles. We evaluate the suitability of synthetic forecasts based on formal probabilistic verification of the operational outcomes. Second, we develop a new synthetic ensemble forecasting algorithm and compare it to a previous algorithm using this validation framework across a set of stylized, hydrologically diverse reservoir systems in California. Results reveal clear differences in operational suitability, with the new method consistently outperforming the previous one. These findings demonstrate the promise of the newer synthetic forecasting approach as a generalizable tool for FIRO policy evaluation and robustness testing. They also underscore the value of the proposed validation framework in benchmarking and guiding future improvements in synthetic forecast development. 

Abstract Deep earthquakes require the cold temperatures found in sinking lithosphere to store elastic strain. It has also been proposed that sufficiently high rates of deformation are also required, regardless of the failure mechanism. However, this strain‐rate hypothesis is based on generic time‐dependent and visco‐plastic subduction models, positing a challenge for direct comparisons to present‐day earthquake observations. Here, we present a new numerical modeling approach incorporating location‐specific visco‐elasto‐plastic models to facilitate direct comparison with deep earthquake observations. We present a Proof‐of‐Concept Model using a 2D synthetic slab to demonstrate that this novel approach can reproduce stress and strain‐rate patterns and the stress orientations from a fully time‐dependent model. Applying this method to a 2D profile through the Tonga‐Kermadec subduction zone we find that variations in strain‐rate correlate with seismicity rate and regions of stress in the slab exceeding 500 MPa. Elasticity in the slab leads to formation of a clearly defined neutral plane extending into the transition zone and creating a narrow region of down‐dip compression along the top portion of the slab which broadens across the full width of the slab only within the deep transition zone. In addition, assuming that the strain‐rate hypothesis is correct, we show that peaks in strain‐rate, which are associated with bends in the slab, could be used to constrain the slab shape beyond the envelope of seismicity. 

Abstract Rock dissolution is a common subsurface geochemical reaction affecting pore space properties, crucial for reservoir stimulation, carbon storage, and geothermal energy. Predictive models for dissolution remain limited due to incomplete understanding of the mechanisms involved. We examine the influence of flow, transport, and reaction regimes on mineral dissolution using 29 time‐resolved data from 3D rocks. We find that initial pore structure significantly influences the dissolution pattern, with reaction rates up to two orders of magnitude lower than batch conditions, given solute and fluid‐solid boundary constraints. Flow unevenness determines the location and rate of dissolution. We propose two models describing expected dissolution patterns and effective reaction rates based on dimensionless metrics for flow, transport, and reaction. Finally, we analyze feedback between evolving flow and pore structure to understand conditions that regulate/reinforce dissolution hotspots. Our findings underscore the major impact of flow arrangement on reaction‐front propagation and provide a foundation for controlling dissolution hotspots. 

BackgroundMicroglia play a critical role in neurodegenerative disorders, such as Alzheimer's disease, where alterations in microglial function may result in pathogenic amyloid-β (Aβ) accumulation, chronic neuroinflammation, and deleterious effects on neuronal function. However, studying these complex factors in vivo, where numerous confounding processes exist, is challenging, and until recently, in vitro models have not allowed sustained culture of critical cell types in the same culture. ObjectiveWe employed a rat primary tri-culture (neurons, astrocytes, and microglia) model and compared it to co-culture (neurons and astrocytes) and mono-culture (microglia) to study microglial function (i.e., motility and Aβ clearance) and proteomic response to exogenous Aβ. MethodsThe cultures were exposed to fluorescently-labeled Aβ (FITC-Aβ) particles for varying durations. Epifluorescence microscopy images were analyzed to quantify the number of FITC-Aβ particles and assess cytomorphological features. Cytokine profiles from conditioned media were obtained. Live-cell imaging was employed to extract microglia motility parameters. ResultsFITC-Aβ particles were more effectively cleared in the tri-culture compared to the co-culture. This was attributed to microglia engulfing FITC-Aβ particles, as confirmed via epifluorescence and confocal microscopy. FITC-Aβ treatment significantly increased microglia size, but had no significant effect on neuronal surface coverage or astrocyte size. Upon FITC-Aβ treatment, there was a significant increase in proinflammatory cytokines in tri-culture, but not in co-culture. Aβ treatment altered microglia motility evident as a swarming-like motion. ConclusionsThe results suggest that neuron-astrocyte-microglia interactions influence microglia function and highlight the utility of the tri-culture model for studies of neuroinflammation, neurodegeneration, and cell-cell communication. 

Abstract The behavior of many plant enzymes depends on the metals and other ligands to which they are bound. A previous study demonstrated that tobacco Rubisco binds almost equally to magnesium and manganese and rapidly exchanges one metal for the other. The present study characterizes the kinetics of Rubisco and the plastidial malic enzyme when bound to either metal. When Rubisco purified from five C₃species was bound to magnesium rather than manganese, the specificity for CO₂over O₂, (S_c/o) increased by 25% and the ratio of the maximum velocities of carboxylation / oxygenation (V_cmax/V_omax) increased by 39%. For the recombinant plastidial malic enzyme, the forward reaction (malate decarboxylation) was 30% slower and the reverse reaction (pyruvate carboxylation) was three times faster when bound to manganese rather than magnesium. Adding 6‐phosphoglycerate and NADP⁺inhibited carboxylation and oxygenation when Rubisco was bound to magnesium and stimulated oxygenation when it was bound to manganese. Conditions that favored RuBP oxygenation stimulated Rubisco to convert as much as 15% of the total RuBP consumed into pyruvate. These results are consistent with a stromal biochemical pathway in which (1) Rubisco when associated with manganese converts a substantial amount of RuBP into pyruvate, (2) malic enzyme when associated with manganese carboxylates a substantial portion of this pyruvate into malate, and (3) chloroplasts export additional malate into the cytoplasm where it generates NADH for assimilating nitrate into amino acids. Thus, plants may regulate the activities of magnesium and manganese in leaves to balance organic carbon and organic nitrogen as atmospheric CO₂fluctuates. 

Abstract Recently, Huang and co‐workers reported a catalytic reaction that utilizes H₂as the sole reductant for a C−C coupling of allyl groups with yields up to 96 %. Here we use computational quantum chemistry to identify several key features of this reaction that provide clarity on how it proceeds. We propose the involvement of a Pd−Pd bound dimer precatalyst, demonstrate the importance of ligand π‐π interactions and counterions, and identify a new, energetically viable, mechanism involving two dimerized, outer‐sphere reductive elimination transition structures that determine both the rate and selectivity. Although we rule out the previously proposed transmetalation step on energetic grounds, we show it to have an unusual aromatic transition structure in which two Pd atoms support rearranging electrons. The prevalence of potential metal‐supported pericyclic reactions in this system suggests that one should consider such processes regularly, but the results of our calculations also indicate that one should do so with caution.