The Prisoner Who Cried Wolf, and Then Swallowed a Sprinkler Head

Case Presentation: A 37-year-old man presented from jail reporting foreign body ingestion of a sprinkler head. While initial radiography did not reveal the foreign body, subsequent imaging with computed tomography demonstrated the sprinkler head. When confronted with this discrepancy the patient admitted to having the sprinkler head in his possession and choosing to swallow it after his initial radiography.Discussion: This case demonstrates the importance of maintaining a high threshold for real illness in situations where there is suspected malingering, a situation not infrequently encountered in the emergency department

The future of auroral E-region plasma turbulence research

The heating caused by ionospheric E-region plasma turbulence has documented global implications for the energy transfer from space into the terrestrial atmosphere. Traveling atmospheric disturbances, neutral wind motion, energy deposition rates, and ionospheric conductance have all been shown to be potentially affected by turbulent plasma heating. Therefore it is proposed to enhance and expand existing ionospheric radar capabilities and fund research into E-region plasma turbulence so that it is possible to more accurately quantify the solar-terrestrial energy budget and study phenomena related to E-region plasma turbulence. The proposed research funding includes the development of models to accurately predict and model the E-region plasma turbulence using particle-in-cell analysis, fluid-based analysis, and hybrid combinations of the two. This review provides an expanded and more detailed description of the past, present, and future of auroral E-region plasma turbulence research compared to the summary report submitted to the National Academy of Sciences Decadal Survey for Solar and Space Physics (Heliophysics) 2024–2033 (Huyghebaert et al., 2022a)

The future of auroral E-region plasma turbulence research

The heating caused by ionospheric E-region plasma turbulence has documented global implications for the energy transfer from space into the terrestrial atmosphere. Traveling atmospheric disturbances, neutral wind motion, energy deposition rates, and ionospheric conductance have all been shown to be potentially affected by turbulent plasma heating. Therefore it is proposed to enhance and expand existing ionospheric radar capabilities and fund research into E-region plasma turbulence so that it is possible to more accurately quantify the solar-terrestrial energy budget and study phenomena related to E-region plasma turbulence. The proposed research funding includes the development of models to accurately predict and model the E-region plasma turbulence using particle-in-cell analysis, fluidbased analysis, and hybrid combinations of the two. This review provides an expanded and more detailed description of the past, present, and future of auroral E-region plasma turbulence research compared to the summary report submitted to the National Academy of Sciences Decadal Survey for Solar and Space Physics (Heliophysics) 2024–2033 (Huyghebaert et al., 2022a)

Examining the Auroral Ionosphere in Three Dimensions Using Reconstructed 2D Maps of Auroral Data to Drive the 3D GEMINI Model

We use the Geospace Environment Model of Ion-Neutral Interactions (GEMINI) to create three-dimensional, time-dependent simulations of auroral ionospheric parameters in the localized, several 100 km region surrounding auroral arcs observed during a winter 2017 sounding rocket campaign, resolving three-dimensional features of fine-scale (km) flow structures in the vicinity of an auroral arc. The three-dimensional calculations of GEMINI allow (with sufficient driving data) auroral current closure to be investigated without idealizing assumptions of sheet-like structures or height integrated ionospheres. Datamaps for two nearly sheet-like arcs are reconstructed from replications of the Isinglass sounding rocket campaign data, and combined with camera-based particle inversions into a set of driving inputs to run the 3D time-dependent model. Comparisons of model results to radar density profiles and to in situ magnetometry observations are presented. Slices of volumetric current, flow, and conductance structures from model outputs are used to interpret closure currents in an auroral arc region, and are compared to original in situ measurements for verification. The predominant source of return current region field aligned current closure for these slow time variation events is seen to be from the conductance gradients, including the Hall. The importance of the versus terms in the determination of the current structure provides a more complicated picture than a previous GEMINI study, which relied predominantly on the divergence of the electric field to determine current structure. Sensitivity of data-driven model results to details of replication and reconstruction processes are discussed, with improvements outlined for future work

An Appalachian Amazon? Magnetofossil evidence for the development of a tropical river-like system in the mid-Atlantic United States during the Paleocene-Eocene thermal maximum

On the mid-Atlantic Coastal Plain of the United States, Paleocene sands and silts are replaced during the Paleocene-Eocene Thermal Maximum (PETM) by the kaolinite-rich Marlboro Clay. The clay preserves abundant magnetite produced by magnetotactic bacteria and novel, presumptively eukaryotic, iron-biomineralizing microorganisms. Using ferromagnetic resonance spectroscopy and electron microscopy, we map the magnetofossil distribution in the context of stratigraphy and carbon isotope data and identify three magnetic facies in the clay: one characterized by a mix of detrital particles and magnetofossils, a second with a higher magnetofossil-to-detrital ratio, and a third with only transient magnetofossils. The distribution of these facies suggests that suboxic conditions promoting magnetofossil production and preservation occurred throughout inner middle neritic sediments of the Salisbury Embayment but extended only transiently to outer neritic sediments and the flanks of the embayment. Such a distribution is consistent with the development of a system resembling a modern tropical river-dominated shelf

The Prisoner Who Cried Wolf, and Then Swallowed a Sprinkler Head

Case Presentation: A 37-year-old man presented from jail reporting foreign body ingestion of a sprinkler head. While initial radiography did not reveal the foreign body, subsequent imaging with computed tomography demonstrated the sprinkler head. When confronted with this discrepancy the patient admitted to having the sprinkler head in his possession and choosing to swallow it after his initial radiography.Discussion: This case demonstrates the importance of maintaining a high threshold for real illness in situations where there is suspected malingering, a situation not infrequently encountered in the emergency department

On the theory of the incoherent scatter gyrolines

The incoherent scatter spectrum feature referred to as the “gyroline” is investigated theoretically and experimentally. The gyroline is associated with the dispersion relation for electrostatic whistler waves. Earlier treatments by Trulsen and Bj⊘rna (1978, and references therein) derive the frequency and growth rate for these waves, but their derivation is only accurate for very small magnetic aspect angles, i.e., for wave vectors close to perpendicular to the geomagnetic field. Their expression for the frequency has the form of a low-order Padé approximate, but we find that a simple formula of this kind accurate for arbitrary magnetic aspect angles does not exist. We therefore analyze the incoherent scatter gyroline feature computationally. The analysis is supported by range-resolved incoherent scatter spectrograms measured recently at Arecibo. The gyroline feature is shown to be strongest in the midlatitude E and valley regions where the electron temperature is low enough to avoid cyclotron damping

Radar observations of thermal plasma oscillations in the ionosphere

Incoherent scatter radar observations of ionospheric plasmas rely on echoes from electron density fluctuations with properties governed by the dispersion relations for ion acoustic and Langmuir waves. Radar observations of echoes associated with Langmuir waves (plasma lines) from thermal plasma are weak, and only a few near‐thermal level measurements have been reported. Plasma line echoes are typically only observed with existing radars only when the Langmuir waves are enhanced by suprathermal electrons. A new observation technique has been developed which is sensitive enough to allow observations of these echoes without the presence of suprathermal electrons up to at least 1000 km. This paper presents recent observations from the Arecibo Observatory 430 MHz incoherent scatter radar which show plasma line echoes during the night when no suprathermal enhancement is expected to be present. The observations are compared with theory, and the results are found to be in agreement with classical incoherent scatter theory for thermal plasmas. The theoretical ratio of the ion line and plasma line power spectral density is within approximately 3 dB of the predicted value. The finding adds a new observational capability, allowing electron density to also be observed at night using the plasma line well into the top side of the ionosphere, increasing the accuracy of the electron density measurement