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The paper presents the effects of the storm‐time prompt penetration electric fields (PPEF) and traveling atmospheric disturbances (TADs) on the total electron content (TEC), foF2 and hmF2 in the American sector (north and south) during the geomagnetic storm on 23–24 April 2023. The data show a poleward shift of the Equatorial Ionization Anomaly (EIA) crests to 18°N and 20°S in the evening of 23 April (attributed to eastward PPEF) and the EIA crests remaining almost in the same latitudes after the PPEF reversed westward. The thermospheric neutral wind velocity, foF2, hmF2, and TEC variations show that TADs from the northern and southern high latitudes propagating equatorward and crossing the equator after midnight on 23 April. The meridional keograms of ΔTEC show the TAD structures in the north/south propagated with phase velocity 470/485 m/s, wave length 4,095/4,016 km and period 2.42/2.30 hr, respectively. The interactions of the TADs also appear to modify the wind velocities in low latitudes. The eastward PPEF and equatorward TADs also favored the development of a clear/not so clear F3 layer in northern/southern regions of the equator. Plain Language Summary: The thermosphere‐ionosphere‐magnetosphere system is largely affected during events of geomagnetic storms. Its dynamics, mainly in the ionized environment, may impact modern lives by degradations in the satellite signals affecting, for example, all applications involving Global Navigation Satellite System. The thermosphere and ionosphere responses to the large geomagnetic storm of 23–24 April 2023 are analyzed here and the main discoveries are the unexpected spatial plasma density distribution over Boa Vista (MLat ≈ 8°N) due to resulting effects of a disturbed eastward electric field and traveling atmospheric disturbance (TAD). The interactions/interferences of TADs were able to explain the unexpected moment of the peak in thermospheric neutral wind speed measurements over the equatorial station, as well as all variations in ionospheric parameters (foF2, hmF2, and total electron content) recorded in pairs by seven Digisondes and GNSS receivers spread across Brazil. Key Points: Interactions of traveling atmospheric disturbances (TADs) cause unexpected thermospheric neutral wind speeds in the American equatorial and low‐latitude sectorsThe effects resulting from a disturbed electric field and TADs were able to produce anomalous electron density distribution at low latitudesThe variations in the ionospheric observational measurements recorded around 4 UT in Brazil on 24 April 2023 were explained by the passages of TADs [ABSTRACT FROM AUTHOR]

The spectral line profile of the atomic oxygen O1D2—3P2 transition near 6300 Å in the airglow has been used for more than 50 years to extract neutral wind and temperature information from the F‐region ionosphere. A new spectral model and recent samples of this airglow emission in the presence of the nearby lambda‐doubled OH Meinel (9‐3) P2(2.5) emission lines underscores earlier cautions that OH can significantly distort the OI line center position and line width observed using a single‐etalon Fabry‐Perot interferometer (FPI). The consequence of these profile distortions in terms of the emission profile line width and Doppler position is a strong function of the selected etalon plate spacing. Single‐etalon Fabry‐Perot interferometers placed in the field for thermospheric measurements have widely varying etalon spacings, so that systematic wind biases caused by the OH line positions differ between instruments, complicating comparisons between sites. Based on the best current determinations of the OH and O1D line positions, the ideal gap for a single‐etalon FPI wind measurements places the OH emissions in the wings of the O1D spectral line profile. Optical systems that can accommodate prefilters with square passbands less than ∼3 Å in the optical beam can effectively block the OH contamination. When that is not possible, a method to fit for OH contamination and remove it in the spectral background of an active Fabry‐Perot system is evaluated. Plain Language Summary: The bulk motion of neutral gas in the ionosphere, neutral winds, redistributes plasma creating regional ionospheric density variations and currents, which further structure ionospheric density and transport. For this reason, measurements of the neutral winds in the thermosphere are important for physics‐based modeling of the ionosphere. This work revisits spectral contamination effects in a common thermospheric wind measurement technique by a nearby emission arising from the OH molecule in the upper mesosphere. Recognition of the contamination and its mitigation are essential for comparisons between and among a globally distributed array of ground‐based wind measuring sites. Key Points: OH airglow is an insidious spectral contaminant for single‐etalon Fabry‐Perot interferometers, distorting the Doppler shape of the thermospheric O1D emissionThe consequences of OH contamination for thermospheric wind and temperature measurements vary widely between current Fabry‐Perot interferometer designsFabry‐Perots minimize systematic 6300 Å Doppler wind errors by using an etalon spacing of 0.8676 cm plus integral multiples of 0.0826 cm [ABSTRACT FROM AUTHOR]

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Abstract: Photoelectron (PE) impact on ground‐state O(3P) atoms is well known as a major source of twilight 844.6 nm emission in the midlatitude thermosphere. Knowledge of the PE flux can be used to infer thermospheric oxygen density, [O], from photometric measurements of 844.6 nm airglow, provided that PE impact is the dominant process generating the observed emission. During several spring observational campaigns at Arecibo Observatory, however, we have observed significant 844.6 nm emission throughout the night, which is unlikely to arise from PE impact excitation which requires solar illumination of either the local or geomagnetically conjugate thermosphere. Here we show that radiative recombination (RR) of O+ ions is likely responsible for the observed nighttime emission, based on model predictions of electron and O+ ion density and temperature by the Incoherent Scatter Radar Ionosphere Model. The calculated emission brightness produced by O + RR exhibits good agreement with the airglow data, in that both decay approximately monotonically throughout the night at similar rates. We conclude that the conventional assumption of a pure PE impact source is most likely to be invalid during dusk twilight, when RR‐generated emission is most significant. Estimation of [O] from measurements of 844.6 nm emission demands isolation of the PE impact source via coincident estimation of the RR source, and the effective cross section for RR‐generated emission is found here to be consistent with optically thin conditions. [ABSTRACT FROM AUTHOR]

Study Objective: Recently published clinical guidelines for the management of febrile children are based on studies that used rectal temperature data to stratify the risk of bacteremia and septic complications. Appropriate management decisions rely on accurate detection and categorization of fever. Accordingly, this study compared the newer infrared tympanic thermometry (ITT) to rectal thermometry in this regard., Design: Prospective observational study., Setting: Urban teaching hospital ED with annual census of 60,000., Participants: Consecutive children 6 months to 6 years old who had rectal temperatures measured., Interventions: Triage nurses recorded rectal temperatures and bilateral ITT temperatures. Temperatures were correlated by Pearson correlation coefficients and compared using paired t tests with significance set at P < .01. Children were categorized by degree of fever using rectal temperature (afebrile, less than 100.4 degrees F; low fever, 100.4 to 102.9 degrees F; and high fever, more than 102.9 degrees F), and the accuracy of ITT in detecting fever and high fever was determined., Results: Three hundred seventy patients were enrolled in the study. The mean age was 18.4 +/- 11.3 months; boys comprised 56% of patients. The mean temperatures were rectal, 101.0 +/- 2.0 degrees F; right tympanic membrane, 100.4 +/- 1.9 degrees F; and left tympanic membrane, 100.3 +/- 1.9 degrees F. The tympanic membrane temperatures were significantly lower than rectal readings (P << .001 for both right and left versus rectal). Rectal temperatures showed good correlation with both right and left tympanic membrane temperatures (r = .83 and .85, respectively). ITT was 76% sensitive and 92% specific in detecting fever of 100.4 degrees F or more (positive predictive value, 0.92; negative predictive value, 0.76). In the detection of high fever, ITT was only 57% sensitive but 98% specific (positive predictive value, 0.90; negative predictive value, 0.90). Rectal and TM temperatures differed by at least 0.5 degree F in 70% of the patients, 1.0 degree F in 41%, 2.0 degrees F in 12%, and 3.0 degrees F in 3%., Conclusion: Despite the statistical correlation between ITT and rectal temperatures, the modalities may yield significantly different temperatures. The poor sensitivity of ITT in detecting fever and high fever may result in clinically important miscategorizations of individual patients. Current clinical management that is based on the presence and height of fever may be adversely affected if ITT is used.

The purpose of this qualitative study was to explore how meanings adult daughters attached to their parent's death influenced the duration of their grief. The sample consisted of 67 adult daughters, ages 35 to 69 years, who had lost a parent 1 to 3 years earlier. Respondents were asked to explore their perceptions about their parent's death, their lifelong parent-daughter relationship, and any lifestyle changes that occurred after a parent's death. Categories were identified from the interview questions, and themes within each category were developed from the interview data. Results indicated that how respondents experienced a parent's death--including their guilt, regrets, or anticipatory grief, shifts in other family relationships, and changes in lifestyle--influenced the duration of their grief. The findings suggest that the subjective experience of grief may be an important area for further research as well as for assessment and intervention.

Objective: The reliability of infrared tympanic thermometry (ITT) in children and the effect of acute otitis media (AOM) on ITT are unsettled. This study assessed the effect of AOM on ITT and the utility of ITT in the diagnosis of AOM., Methods: 520 consecutive children, aged 6 months to 6 years, presenting to the ED of an urban teaching hospital were eligible for this prospective observational study. Nurses recorded oral or rectal reference temperatures (RefTs) and bilateral ITT temperatures upon presentation. Emergency physicians were blinded to the ITT temperatures. AOM was diagnosed according to published clinical criteria., Results: Among 520 patients, 108 had unilateral AOM and 78 had bilateral AOM. In patients with unilateral AOM, the infected ears were warmer (I = 100.4 +/- 1.8 degrees F) than the uninfected ears (U = 100.3 +/- 1.8 degrees F, p = 0.035). However, the disparity in TM temperatures in infected and uninfected ears with unilateral AOM (I - U = 0.2 +/- 0.9 degrees F) was similar to the difference between right and left ears in those without AOM (R - L = 0.1 +/- 0.8 degrees F, p = 0.60). Compared with patients without AOM, patients with AOM demonstrated no significant elevation of ITT temperatures over RefTs (I - RefT = -0.8 +/- 1.2 degrees F in AOM; ITT - RefT = -0.8 +/- 1.2 degrees F in non-AOM; p = 0.94). This study had >99% power to detect a 1.0 degrees F difference for all groups compared., Conclusions: Infrared tympanic temperature are not helpful in diagnosing AOM in children. AOM has little direct effect on ITT temperatures.