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Abstract In aquatic ecosystems, greater food web complexity is theorized to increase persistence and resilience of primary production to pulse disturbances, yet experimental evidence is limited. We simulated two storm‐induced pulse disturbances by adding nutrients (~ 3%–5% increase in ambient concentrations) to three ponds with low, intermediate, and high food web complexity and compared to reference ponds. We evaluated the ecological stability of primary production by quantifying persistence as the number of days it took chlorophyll‐aor ecosystem metabolism to deviate significantly from reference conditions and resilience as the time to recover to reference conditions following each disturbance. We also evaluated if a critical transition occurred following the disturbance. The high complexity pond did not significantly deviate from reference conditions following either nutrient pulse, suggesting high ecological stability. The intermediate complexity pond had lower stability, with persistence relatively consistent at 18 and 24 d after each nutrient pulse, and resilience trending toward a substantial increase from 23 d to less than a week before the experiment concluded. Stability was lowest in the low complexity pond where persistence decreased from 24 d to just 8 d and resilience decreased from 5 to 22 d. There was also evidence of a critical transition after the first pulse in the low complexity pond, but not for higher complexity ponds. This experiment provides strong support that food web connectivity and food chain length can aid in buffering aquatic ecosystems against increasing and intensifying by influencing persistence and resilience to repeated nutrient pulses. 

We use randomized treatments that provide different types of information about the first and/or second moments of future economic growth to generate exogenous changes in the perceived macroeconomic uncertainty of treated households. The effects on their spending decisions relative to an untreated control group are measured in follow-up surveys. Our results indicate that, after taking into account first moments, higher macroeconomic uncertainty induces households to significantly and persistently reduce their total monthly spending in subsequent months. Changes in spending are broad based across spending categories and apply to larger durable good purchases as well. (JEL D12, D81, D84, E21, E23, G51) 

Abstract We examine a century of radial velocity, visual magnitude, and astrometric observations of the nearest red supergiant, Betelgeuse, in order to reexamine the century-old assertion that Betelgeuse might be a spectroscopic binary. These data reveal Betelgeuse varying stochastically over years and decades due to its boiling, convective envelope, periodically with a 5.78 yr long secondary period (LSP), and quasiperiodically from pulsations with periods of several hundred days. We show that the LSP is consistent between astrometric and radial velocity data sets, and argue that it indicates a low-mass companion to Betelgeuse, less than a solar mass, orbiting in a 2110 day period at a separation of just over twice Betelgeuse’s radius. The companion star would be nearly 20 times less massive and a million times fainter than Betelgeuse, with similar effective temperature, effectively hiding it in plain sight near one of the best-studied stars in the night sky. The astrometric data favor an edge-on binary with orbital plane aligned with Betelgeuse’s measured spin axis. Tidal spin–orbit interaction drains angular momentum from the orbit and spins up Betelgeuse, explaining the spin–orbit alignment and Betelgeuse’s anomalously rapid spin. In the future, the orbit will decay until the companion is swallowed by Betelgeuse in the next 10,000 yr. 

The seminal work of Jonung (1981) showed that households' perceptions of inflation are the strongest predictor of households' inflation expectations. This fact has been a key ingredient for testing and developing theoretical models of how economic agents form expectations (e.g., the famous Lucas (1972) island model). However, little is known about whether perceptions play a similar role for firms. Using a new survey of American CEOs, we document that inflation perceptions shape the inflation expectations of firms just as Jonung (1981) found for households. These results suggest that information rigidities apply not only for households but also for CEOs. 

Abstract We document an apparent downward displacement of the Matuyama‐Brunhes magnetic reversal by ∼20 m at Scotia Sea International Ocean Discovery Program Site U1538 (Pirie Basin) by comparison with the well‐defined paleomagnetic record at nearby Site U1537 (Dove Basin). Detailed stratigraphic correlation between the two sites is possible due to similar lithologic variations. However, the two sites have distinctly different porewater geochemistry. Notably, Site U1538 indicates a greater demand for electron acceptors to oxidize organic carbon and Fe²⁺enrichment below the depth of SO₄²⁻depletion. Magnetic parameters indicate enrichment of an authigenic magnetic mineral with strong remanence properties around the depth of SO₄²⁻depletion (∼46 m at Site U1538) relative to magnetic parameters at correlative depths at Site U1537. Fe²⁺enrichment below the depth of SO₄²⁻depletion is not predicted based on the energetically favorable order of electron acceptors for microbial respiration but is documented here and in other depositional settings. This indicates Fe²⁺production exceeds the production of H₂S by SO₄²⁻reduction, providing a geochemical environment that favors the production and preservation of ferrimagnetic remanence‐bearing iron sulfides over paramagnetic pyrite and, thus, a mechanism for deep chemical remanent magnetization acquisition at depths of tens of meters. The influence of authigenic ferrimagnetic iron sulfides on paleomagnetic signals can be difficult to demonstrate with magnetic properties alone; therefore, this finding has implications for evaluating the fidelity of magnetostratigraphic records with complementary geochemical data. Such situations should be considered in other depositional environments with similar porewater Fe²⁺accumulation below the SO₄²⁻reduction depth. 

Abstract We compare causal effects of forward guidance about future interest rates on households’ expectations of inflation and nominal mortgage rates to the effects of communication about inflation in a randomized control trial using more than 20,000 U.S. consumers in the Nielsen Homescan Panel. We elicit consumers’ expectations, and then provide 22 different forms of information regarding past, current, and/or future interest rates and inflation. Information treatments about current or future interest rates all have similar and offsetting effects on interest rate and inflation expectations, yielding limited pass-through into perceived real rates. Information about mortgage rates has much more powerful effects on interest rate perceptions, with no offsetting effects on inflation expectations, thereby delivering much larger changes in perceived real rates. Revisions in perceived real rates causally lead to changes in the ex-post purchases of durable goods by households. 

{"Abstract":["Rock magnetic data from IODP Exp. 382 Sites U1537 and U1538 to support Reilly et al. "A geochemical mechanism for >10 m offsets of magnetic reversals inferred from the comparison of two Scotia Sea drill sites"\nExcel Files:\n\nU1537_CubeSummary_Zenodo.xlsx : Summary of NRM, ARM, IRM, and magnetic susceptibility investigations on U1537 cube samples\nU1538_CubeSummary_Zenodo.xlsx : Summary of NRM, ARM, IRM, and magnetic susceptibility investigations on U1538 cube samples\nZip Files:\n\nFORC_Data.zip : First order reversal curve data files in MicroMag format for samples discussed in paper\nDCD_Data.zip : DC Demagnetization curve data files for samples discussed in paper\nHysteresis_Data.zip : Hysteresis Loops for samples discussed in paper\nMPMS_Data.zip : Data collected on Magnetics Property Measurement System 3, including Field Cooled/Zero Field Cooled Curves, Low Temperature Cycling of Room Temperature IRM, and AC Susceptibility\n \nNRM = Natural Remanent Magnetization; ARM = Anhysteretic Remanent Magnetization; IRM = Isothermal Remanent Magnetization"]}