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  Climate of an ultra hot Jupiter: Spectroscopic phase curve of WASP-18b with HST/WFC3

  Arcangeli, Jacob; Désert, Jean-Michel; Parmentier, Vivien; Stevenson, Kevin B.; Bean, Jacob L.; Line, Michael R.; Kreidberg, Laura; Fortney, Jonathan J.; Showman, Adam P.; Univ Arizona, Dept Planetary Sci; et al. (EDP SCIENCES S A, 2019-05-28)

  We present the analysis of a full-orbit, spectroscopic phase curve of the ultra hot Jupiter (UHJ) WASP-18b, obtained with the Wide Field Camera 3 aboard the Hubble Space Telescope. We measured the normalised day-night contrast of the planet as >0.96 in luminosity: the disc-integrated dayside emission from the planet is at 964 +/- 25 ppm, corresponding to 2894 +/- 30 K, and we place an upper limit on the nightside emission of <32 ppm or 1430 K at the 3 sigma level. We also find that the peak of the phase curve exhibits a small, but significant offset in brightness of 4.5 +/- 0.5 degrees eastward. We compare the extracted phase curve and phase-resolved spectra to 3D global circulation models and find that broadly the data can be well reproduced by some of these models. We find from this comparison several constraints on the atmospheric properties of the planet. Firstly we find that we need efficient drag to explain the very inefficient day-night recirculation observed. We demonstrate that this drag could be due to Lorentz-force drag by a magnetic field as weak as 10 gauss. Secondly, we show that a high metallicity is not required to match the large day-night temperature contrast. In fact, the effect of metallicity on the phase curve is different from cooler gas-giant counterparts because of the high-temperature chemistry in the atmosphere of WASP-18b. Additionally, we compared the current UHJ spectroscopic phase curves, WASP-18b and WASP-103b, and show that these two planets provide a consistent picture with remarkable similarities in their measured and inferred properties. However, key differences in these properties, such as their brightness offsets and radius anomalies, suggest that UHJ could be used to separate between competing theories for the inflation of gas-giant planets.
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  Gallbladder Perforation Secondary to Enteric Fever: An Interesting Case of Acute Abdomen

  Malik, Mustafa N; Mahmood, Tayyab; Tameez Ud Din, Asim; Aslam, Shehroz; Imtiaz, Maria; Univ Arizona, Internal Med (CUREUS INC, 2019-04-22)

  Enteric fever is a common infectious disease, especially in countries with poor sanitation and in the tropics. It is caused mainly by Salmonella typhi and accounts for nearly 27 million cases worldwide and 200,000 deaths annually. Enteric fever involves the reticuloendothelial system such as bone marrow, spleen, and liver. As it mostly involves the Peyer's patches of the terminal ileum, enteric perforation occurs commonly. However, gallbladder perforation can also occur, though not very often. Ultrasound as well as computerized tomography (CT) abdomen and pelvis lack specificity for detecting gallbladder perforations in enteric fever. Diagnosis is usually confirmed intraoperatively when the gallbladder is visualized and perforation is seen. Gallbladder perforation is usually seen in acute cholecystitis when the gallbladder becomes necrotic and gangrenous. In acalculous cholecystitis, perforation is rare. Enteric fever is one of the rarest causes of acalculous cholecystitis, leading to perforation. Here, we present the case of a 20-year-old man who presented with fever for 10 days along with loose stools, vomiting, and acute abdomen. Labs showed leukopenia, positive Typhidot test but X-ray erect abdomen and ultrasound abdomen and pelvis were nonspecific. Only after resuscitation and exploration of the abdomen was it found that the gallbladder had multiple perforations. The patient was improved after eight days of postoperative intravenous antibiotics. This is a unique and rare presentation of such a common infectious disease.
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  Development of a Medical Student Cardiopulmonary Resuscitation Elective to Promote Education and Community Outreach

  Panchal, Ashish; Keim, Samuel; Ewy, Gordon; Kern, Karl; Hughes, Kate E; Beskind, Daniel; Univ Arizona, Emergency Med (CUREUS INC, 2019-04-20)

  Introduction: One of the barriers to improving cardiac arrest survival is the low rate of cardiopulmonary resuscitation (CPR) provision. Identifying this as a public health issue, many medical students often assist in training the community in CPR. However, these experiences are often short and are not associated with structured resuscitation education, limiting the student's and the community's learning. In this assessment, we identified a need and developed a curriculum, including defined goals and objectives, for an undergraduate medical education (UME) elective in CPR. Methods: At an academic university environment with a strong UME program, we developed a longitudinal UME elective in CPR. The curriculum is a four-year longitudinal experience, which satisfies two weeks of their fourth year of medical school. The curriculum includes structured training over the four-year period in the fundamentals of resuscitation science (through didactics, journal club, and hands-on skills training), in addition to structured community CPR teaching. The elective concludes with a final hands-on summative appraisal. Data concerning medical student program enrollment, CPR training events conducted, venues of events, and the number of individuals trained were collected over a five-year period. Results: The CPR elective was developed with clear goals and objectives based on identified needs. Over the five-year period, 186 medical students completed the CPR longitudinal elective, accounting for 8.4% of the total medical student population. Students completed curriculum requirements and satisfied both didactic and hands-on training with all students passing the final summative appraisal. Over the five-year period, students trained 8,694 people in bystander CPR. The summative evaluation had a 100% pass rate. Conclusion: Implementation of a longitudinal CPR elective improved resuscitation science education for medical students and fostered increased community CPR training. This describes one local effort to improve resuscitation science education and training for medical students. Further work will need to be done to evaluate the impact of UME resuscitation curricula on medical student career choice and resuscitation outcomes.
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  Initial data for general relativistic simulations of multiple electrically charged black holes with linear and angular momenta

  Bozzola, Gabriele; Paschalidis, Vasileios; Univ Arizona, Dept Phys; Univ Arizona, Dept Astron (AMER PHYSICAL SOC, 2019-05-17)

  A general relativistic, stationary, and axisymmetric black hole in a four-dimensional asymptotically flat spacetime is fully determined by its mass, angular momentum, and electric charge. The expectation that astrophysically relevant black holes do not posses charge has resulted in a limited number of investigations of moving and charged black holes in the dynamical, strong-field gravitational (and electromagnetic) regime, in which numerical studies are necessary. Apart from having a theoretical interest, the advent of multimessenger astronomy with gravitational waves offers new ways to think about charged black holes. In this work, we initiate an exploration of charged binary black holes by generating valid initial data for general relativistic simulations of black hole systems that have generic electric charge and linear and angular momenta. We develop our initial data formalism within the framework of the conformal transversetraceless (Bowen-York) technique using the puncture approach and apply the theory of isolated horizons to attribute physical parameters (mass, charge, and angular momentum) to each hole. We implemented our formalism in the case of a binary system by modifying the publicly available TWOPUNCTURES and QUASILOCALMEASURES codes. We demonstrate that our code can recover existing solutions and that it has excellent self-convergence properties for a generic configuration of two black holes.
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  Dark matter interpretation of the ANITA anomalous events

  Heurtier, Lucien; Mambrini, Yann; Pierre, Mathias; Univ Arizona, Dept Phys (AMER PHYSICAL SOC, 2019-05-17)

  The ANITA collaboration recently reported the detection of two anomalous upward-propagating extensive air showers exiting the Earth with relatively large emergence angles and energies in the range O(0.5-1) EeV. We interpret these two events as coming from the decay of a massive dark matter candidate (m(DM) greater than or similar to 10(9) GeV) decaying into a pair of right-handed neutrinos. While propagating through the Earth, these extremely boosted decay products convert eventually to tau-leptons which lose energy during their propagation and produce showers in the atmosphere detectable by ANITA at emergence angles larger than what Standard Model neutrinos could ever produce. We performed Monte Carlo simulations to estimate the propagation and energy loss effects and derived differential effective areas and number of events for the ANITA and the IceCube detectors. Interestingly, the expected number of events for IceCube is of the very same order of magnitude as the number of events observed by ANITA but at larger emergence angles, and energies less than or similar to 0.1 EeV. Such features match perfectly with the presence of the two upward-going events IceCube-140109 and IceCube-121205 that have been exhibited from a recent reanalysis of IceCube data samples.

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