Photoemission and electrostatic potentials on the dayside lunar surface in the terrestrial magnetotail lobes.

Despite the need to accurately predict and assess the lunar electrostatic environment in all ambient conditions that the Moon encounters, photoemission and electrostatic potentials on the dayside lunar surface in the terrestrial magnetotail lobes remain poorly characterized. We study characteristics and variabilities of lunar photoelectron energy spectra by utilizing Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) and Apollo measurements in combination with the Flare Irradiance Spectral Model (FISM). We confirm that the photoelectron spectral shapes are consistent between ARTEMIS and Apollo and that the photoelectron flux is linearly correlated with the FISM solar photon flux. We develop an observation-based model of lunar photoelectron energy distributions, thereby deriving the current balance surface potential. The model predicts that dayside lunar surface potentials in the tail lobes (typically tens of volts) could increase by a factor of 2 - 3 during strong solar flares.

MAVEN observations of the response of Mars to an interplanetary coronal mass ejection.

Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere.

Early MAVEN Deep Dip campaign reveals thermosphere and ionosphere variability.

The Mars Atmosphere and Volatile Evolution (MAVEN) mission, during the second of its Deep Dip campaigns, made comprehensive measurements of martian thermosphere and ionosphere composition, structure, and variability at altitudes down to ~130 kilometers in the subsolar region. This altitude range contains the diffusively separated upper atmosphere just above the well-mixed atmosphere, the layer of peak extreme ultraviolet heating and primary reservoir for atmospheric escape. In situ measurements of the upper atmosphere reveal previously unmeasured populations of neutral and charged particles, the homopause altitude at approximately 130 kilometers, and an unexpected level of variability both on an orbit-to-orbit basis and within individual orbits. These observations help constrain volatile escape processes controlled by thermosphere and ionosphere structure and variability.

Appropriateness of endotracheal tube size and insertion depth in children undergoing air medical transport.

OBJECTIVES: Guidelines for pediatric endotracheal tube (ETT) size and insertion depth are important in the helicopter EMS (HEMS) setting, where intubated patients are frequently transported by a non-physician flight crew providing protocol-based care in an environment noted for limitations in clinical airway assessment. The objectives of this study were to characterize, in a HEMS pediatric population, the frequency of compliance with guideline-recommended ETT size and insertion depth, and to test for association between guideline noncompliance and subsequent receiving hospital adjustment of ETT size or insertion depth. DESIGN: This retrospective review analyzed 216 consecutive pediatric (age <14) scene and interfacility HEMS transports, of patients intubated before or during HEMS transport, by an urban two-helicopter HEMS service providing protocol-based care with a nurse/paramedic crew configuration. Patients were transported to one of three receiving academic pediatric referral centers. Pediatric Advanced Life Support (PALS) criteria for ETT size and insertion depth were used to assess guideline-appropriateness of pediatric ETTs. Receiving hospital records were reviewed to determine if post-transport ETT size or lipline adjustment were associated with guideline-appropriateness of size and lipline during HEMS transport. Univariate (chi-square and Fisher's exact) and multivariate (logistic regression) statistics were used to assess and control for the following covariates: intubator group (physician, flight crew, ground EMS), transport year, sex, age, transport type (scene versus interfacility), and receiving hospital. For all analyses, statistical significance was set at the 0.05 level. RESULTS: The initial ETT size was within 0.5 mm of guideline-recommended sizes in 178 (83.6%) of the 213 patients for whom this data were available. Inappropriate sized ETTs were nearly always (32 of 35, 91.4%) too small. Compared to initial ETTs placed by ground EMS personnel, initial ETTs placed by flight crew or physicians were more likely to be appropriate as defined by guidelines (P = .008 and .032, respectively). Receiving hospitals changed the ETT size in 18 (8.3% of 216) cases. Receiving hospital ETT size change was more likely with later transport year (P = .018) and less likely in patients over 2 years of age (P = .03); there was no significant association between receiving hospital ETT size change and intubator group (P > .22) or guideline-appropriateness of ETT size (P = 0.94). The initial ETT insertion depth was within 1 cm of the guideline-recommended lipline in 86 (43.2%) of the 199 patients for whom this data were available. Inappropriate liplines were almost always (109 of 113, 96.5%) too deep. Compared to initial ETT liplines determined by ground EMS personnel, initial liplines determined by flight crew (P = .007), but not physician (P = .47) were more likely to be appropriate as defined by guidelines. Receiving hospitals changed the ETT insertion depth in 72 (33.3% of 216) cases. Receiving hospital lipline change was more likely (P = .03) in patients older than 2 years of age, but was not associated with intubator group (P = .75) or lipline guideline-appropriateness (P = .35). CONCLUSIONS: As judged by frequently used guidelines, pediatric ETTs are often too small and commonly inserted too deep. However, this retrospective study, limited by lack of clinical correlation for ETT size and insertion depth, failed to find an association between lack of ETT size or lipline guideline compliance and subsequent ETT adjustment at receiving pediatric centers. This study's findings, which should be confirmed with prospective investigation, cast doubt upon the utility of pediatric ETT size/lipline guidelines as strict clinical or quality assurance tools for use in pediatric airway management.

Relations of exercise to body image and sexual desirability among a sample of university students.

College students (N = 212) completed a survey designed to elicit information about their exercise habits, perceived sexual desirability, and body image. A number of body-image items were associated with both perceived physical attractiveness and perceived sexual desirability. Total body image was related to gender, exercise level, perceived physical attractiveness, perceived sexual desirability, and perception of self as a sexual partner.

Detection and confirmation of cocaine and cocaethylene in serum emergency toxicology specimens.

We report the performance of a liquid chromatography (LC) assay for detection and confirmation of cocaine and cocaethylene in serum. A photodiode array (PDA) detector monitors the cyano column effluent at 230 nm for analyte detection. Confirmation of a peak's identity is performed by use of only the 226-254-nm segment of the spectra rather than a broader range such as 210-340 nm. Use of the narrower range improves the assay's sensitivity by almost 10-fold. Analyte values of 10 micrograms/L are confirmed routinely. Intra-assay imprecision at 100, 20, and 10 micrograms/L for cocaine is 5.1%, 5.7%, and 6.6% (CV), respectively. Absolute recovery of the analytes exceeds 80%. In a split-sample study (33 positives and 74 negatives), each of this method's cocaine findings were confirmed. Cocaethylene was found in 15 of these samples. A complete chromatogram can be available 15 min after the start of the procedure. The method's focus on the active drug (rather than urinary metabolites) and its ability to detect and confirm many other drugs make it well suited for emergency toxicology testing.

Management of pituitary-adrenal suppression secondary to corticosteroid therapy.

Withdrawal of steroid medications from patients who have been receiving them for management of chronic disease carries the risk of certain serious complications. An understanding of adrenal physiology, coupled with a rational plan for evaluating the individual patient, when necessary, and for protecting against certain stressful situations, should obviate the occurrence of acute adrenal insufficiency.

Planning a shared-schedule residency.

Shared-schedule residency training has received more consideration recently as more people have become aware of the need and desirability of such programs. The details of one program, in the Department of Pediatrics of the University of Texas Medical Branch at Galveston, are reviewed. Some of the problems encountered in the execution of this type of program are presented, along with some suggestions for their alleviation. The benefits of a shared-schedule residency are also discussed. The authors suggest guidelines to use in planning a shared-schedule residency program.