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Increasing the resilience of agricultural landscapes requires fundamental changes to the dominant commodity production model, including incorporating practices such as reduced tillage, cover cropping, and extended rotations that reduce soil disturbance while increasing biological diversity. Increasing farmer adoption of these conservation systems offers the potential to transform agriculture to a more vibrant, resilient system that protects soil, air, and water quality. Adoption of these resilience practices is not without significant challenges. This paper presents findings from a participatory effort to better understand these challenges and to develop solutions to help producers overcome them. Through repeated, facilitated discussions with farmers and agricultural and conservation professionals across the U.S. state of Michigan, we confronted the policy, economic, and structural barriers that are inhibiting broader adoption of conservation systems, as well as identified policies, programs, and markets that can support their adoption. What emerged was a complex picture and dynamic set of challenges at multiple spatial scales and across multiple domains. The primary themes emerging from these discussions were barriers and opportunities, including markets, social networks, human capital, and conservation programs. Exacerbating the technical, agronomic, and economic challenges farmers face at the farm level, there are a host of community constraints, market access and availability problems, climatic and environmental changes, and policies (governmental and corporate) that cross‐pressure farmers when it comes to making conservation decisions. Understanding these constraints is critical to developing programs, policies, and state and national investments that can drive adoption of conservation agriculture.

 

Abstract We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.°2 away from the best-fit position of the IceCube neutrino event IceCube-211208A detected on 2021 December 8. The source was in a high-flux state in the optical, ultraviolet, X-ray, and GeV γ -ray bands around the time of the neutrino event, exhibiting daily variability in the soft X-ray flux. The X-ray data from Swift-XRT and NuSTAR characterize the transition between the low-energy and high-energy components of the broadband spectral energy distribution (SED), and the γ -ray data from Fermi-LAT, VERITAS, and H.E.S.S. require a spectral cutoff near 100 GeV. Both the X-ray and γ -ray measurements provide strong constraints on the leptonic and hadronic models. We analytically explore a synchrotron self-Compton model, an external Compton model, and a lepto-hadronic model. Models that are entirely based on internal photon fields face serious difficulties in matching the observed SED. The existence of an external photon field in the source would instead explain the observed γ -ray spectral cutoff in both the leptonic and lepto-hadronic models and allow a proton jet power that marginally agrees with the Eddington limit in the lepto-hadronic model. We show a numerical lepto-hadronic model with external target photons that reproduces the observed SED and is reasonably consistent with the neutrino event despite requiring a high jet power. 

Electron density measured at high latitudes by the Swarm satellites is compared with the measurements by the RISR incoherent scatter radars as the satellites fly by the radars' field of views near Resolute Bay, Canada between 2014 and 2019. More than 200 satellite passes crossing multiple radar beams are considered. Overall, the Swarm‐based electron densities are smaller than those measured by the radars by ∼30%. The values are closer to one another at electron densities betweenand, corresponding to plasma frequencies between 1.5 and 3.5 MHz. Swarm‐measured values are getting progressively smaller than those measured by radars at larger electron densities/plasma frequencies. For the entire range of measured electron densities, the slope of the best fit linear line to the data expressed in terms of electron density is ∼0.62 and offset is. Stronger differences between the instruments were found for observations at nighttime and dawn.

 

ABSTRACT A deep survey of the Large Magellanic Cloud at ∼0.1–100 TeV photon energies with the Cherenkov Telescope Array is planned. We assess the detection prospects based on a model for the emission of the galaxy, comprising the four known TeV emitters, mock populations of sources, and interstellar emission on galactic scales. We also assess the detectability of 30 Doradus and SN 1987A, and the constraints that can be derived on the nature of dark matter. The survey will allow for fine spectral studies of N 157B, N 132D, LMC P3, and 30 Doradus C, and half a dozen other sources should be revealed, mainly pulsar-powered objects. The remnant from SN 1987A could be detected if it produces cosmic-ray nuclei with a flat power-law spectrum at high energies, or with a steeper index 2.3–2.4 pending a flux increase by a factor of >3–4 over ∼2015–2035. Large-scale interstellar emission remains mostly out of reach of the survey if its >10 GeV spectrum has a soft photon index ∼2.7, but degree-scale 0.1–10 TeV pion-decay emission could be detected if the cosmic-ray spectrum hardens above >100 GeV. The 30 Doradus star-forming region is detectable if acceleration efficiency is on the order of 1−10 per cent of the mechanical luminosity and diffusion is suppressed by two orders of magnitude within <100 pc. Finally, the survey could probe the canonical velocity-averaged cross-section for self-annihilation of weakly interacting massive particles for cuspy Navarro–Frenk–White profiles.