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The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90°E and 90°W, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere.

The MAVEN spacecraft launched in November 2013, arrived at Mars in September 2014, and completed commissioning and began its one-Earth-year primary science mission in November 2014. The orbiter’s science objectives are to explore the interactions of the Sun and the solar wind with the Mars magnetosphere and upper atmosphere, to determine the structure of the upper atmosphere and ionosphere and the processes controlling it, to determine the escape rates from the upper atmosphere to space at the present epoch, and to measure properties that allow us to extrapolate these escape rates into the past to determine the total loss of atmospheric gas to space through time. These results will allow us to determine the importance of loss to space in changing the Mars climate and atmosphere through time, thereby providing important boundary conditions on the history of the habitability of Mars. The MAVEN spacecraft contains eight science instruments (with nine sensors) that measure the energy and particle input from the Sun into the Mars upper atmosphere, the response of the upper atmosphere to that input, and the resulting escape of gas to space. In addition, it contains an Electra relay that will allow it to relay commands and data between spacecraft on the surface and Earth.

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.

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.

Epiglottitis is an acute inflammatory condition involving the epiglottis and other supraglottic structures that may lead to airway obstruction. Historically, this condition primarily affected the pediatric population and was secondary to (Hib) infection. Since the vaccination program against Hib serotype B started at age two months, the number of affected pediatric patients has seen a drastic decline. Epiglottitis is now a condition that primarily affects adults. This case report presents a 58-year-old fully vaccinated female presenting with severe throat pain, odynophagia, subjective dyspnea, and chills for two days. During her evaluation, the patient underwent bedside nasopharyngoscopy by the emergency medicine team and was treated appropriately prior to evaluation by an otolaryngologist (ENT). The patient underwent a second nasopharyngoscopy with ENT 75 minutes after the original, which demonstrated vast improvements in the patient's clinical picture, allowing her to avoid intubation. This report highlights the importance of having epiglottitis on the differential for adults, the importance of the emergency medicine physician in performing nasopharyngoscopy, and early intervention with antibiotics and corticosteroids* to improve patient outcomes.

Planetary atmospheric aerobraking will most likely be incorporated in every future Mars orbiting mission. Aerobraking requires an intensive workload during operations. To provide safe and efficient aerobraking, both navigation and spacecraft system teams must be extremely diligent in updating spacecraft sequences and performing periapsis raise or lower maneuvers to maintain the required orbital energy reduction without exceeding the design limits of the spacecraft. Automating the process with onboard measurements could significantly reduce the operational burden and, in addition, could reduce the potential for human error. Two levels of automation are presented and validated using part of the Mars Global Surveyor aerobraking sequence and a simulated Mars Odyssey sequence. The simplest method only provides the capability to update the onboard sequence. This method uses onboard accelerometer measurements to estimate the change in orbital period during an aerobraking pass and thereby estimates the beginning of the next aerobraking sequence. Evaluation of the method utilizing MGS accelerometer data showed that the time of the next periapsis can be estimated to within 25% 3σ of the change in the orbital period due to drag. The second approach provides complete onboard orbit propagation. A low-order gravity model is proposed that is sufficient to provide periapsis altitude predictions to within 100–200 meters over three orbits. Accelerometer measurements are used as part of the trajectory force model while the spacecraft is in the atmosphere.

Atmospheric density data taken during the Mars Global Surveyor aerobraking mission (1997–1999) showed significant variability over the altitude ranges (100–140 km) of interest for aerobraking. This paper presents the method by which Mars Global Surveyor data were used to determine the statistical distribution of mean density and the amplitude and phase of stationary atmospheric waves as a function of latitude. The combination of mean density and waves produced a good fit to the observed data. Using this information, a model was developed to implement the variations into Monte Carlo simulations for future missions to Mars, specifically the Mars Odyssey aerobraking mission (October, 2001–January, 2002). An example of Monte Carlo results for the Mars Odyssey aerobraking mission is shown.

This paper describes a study of first year graduate social work students' work in practica and assesses their transfer of practice evaluation knowledge and skills from the classroom to the field. The data are drawn from case material recorded by the students using a structured recording format. The paper addresses three central questions. What were the salient features of the students' practices? Did students apply practice evaluation knowledge to their work with clients? And, what variables influenced the ways that the students practiced? Recommendations for enhancing class and field integration and for increasing knowledge and skill transfer given the significant influence of the practicum instructor's orientation are discussed.

Atmospheric drag measurements obtained from the study of the orbital decay of Pioneer Venus 1 indicate that atomic oxygen predominates in the Venus atmosphere above 160 kilometers. Drag measurements give evidence that conditions characteristic of a planetary thermosphere disappear near sundown, with inferred exospheric temperatures sharply dropping from approximately 300 K to less than 150 K. Observed densities are generally lower than given by theoretical models.

During the last 2 weeks of February 1977, an intensive scientific investigation of the martian satellite Phobos was conducted by the Viking Orbiter-1 (VO-1) spacecraft. More than 125 television pictures were obtained during this period and infrared observations were made. About 80 percent of the illuminated hemisphere was imaged at a resolution of about 30 meters. Higher resolution images of limited areas were also obtained. Flyby distances within 80 kilometers of the surface were achieved. An estimate of the mass of Phobos (GM) was obtained by observing the effect of Phobos's gravity on the orbit of VO-1 as sensed by Earth-based radiometric tracking. Preliminary results indicate a value of GM of 0.00066 ± 0.00012 cubic kilometer per second squared (standard deviation of 3) and a mean density of about 1.9 ± 0.6 gram per cubic centimeter (standard deviation of 3). This low density, together with the low albedo and the recently determined spectral reflectance, suggest that Phobos is compositionally similar to type I carbonaceous chondrites. Thus, either this object formed in the outer part of the asteroid belt or Lewis's theory that such material cannot condense at 1.5 astronomical units is incorrect. The data on Phobos obtained during this first encounter period are comparable in quantity to all of the data on Mars returned by Mariner flights 4, 6, and 7.