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We propose a new method to estimate ion escape from unmagnetized planets that combines observations and models. Assuming that upstream solar wind conditions are known, a computer model of the interaction between the solar wind and the planet is executed for different ionospheric ion production rates. This results in different amounts of mass loading of the solar wind. We then obtain the ion escape rate from the model run that best fits observations of the bow shock location. As an example of the method, we estimate the heavy-ion escape from Mars on 1 March 2015 to be 2×1024 ions s -1 , using a hybrid plasma model and observations by the Mars Atmosphere and Volatile Evolution (MAVEN) and Mars Express (MEX) missions. This method enables studies on how escape depends on different parameters as well as studies on escape rates during extreme solar wind conditions; moreover, the technique is applicable to studies of escape in the early solar system and at exoplanets. [ABSTRACT FROM AUTHOR]

Looking at the Mars–solar wind interaction on a larger spatial scale than the near Mars region, the planet can be seen as an ion source interacting with the solar wind, in many ways like a comet, but with a smaller ion source region. Here we study the interaction between Mars and the solar wind using a hybrid model (particle ions and fluid electrons). We find that the solar wind is disturbed by Mars out to 100 Mars radii downstream of the planet, and beyond. On this large scale it is clear that the escaping ions can be classified into two different populations. A polar plume of ions picked-up by the solar wind, and a more fluid outflow of ions behind the planet. The outflow increases linearly with the production up to levels of observed outflow rates, then the escape levels off for higher production rates. [ABSTRACT FROM AUTHOR]

Conclusion. The importance of clinical findings in the nose and throat, including fiberoptic endoscopy during the Muller maneuver, in predicting sleep apnea is greater in normal-weight than in overweight women. Objectives. The aim of this study was to identify clinical features that could predict sleep apnea in women. Method. From 6817 women who previously answered a questionnaire concerning snoring habits, 230 women who reported habitual snoring and 170 women from the whole cohort went through a full-night polysomnography. A nose and throat examination including fiber endoscopic evaluation of the upper airways during the Muller maneuver was performed in a random selection of 132 women aged 20–70 years. Results. Sleep apnea was defined as an apnea-hypopnea index of ≥ 10. The influence of clinical features on the prevalence of sleep apnea varied between normal-weight and overweight women. A low soft palate, retrognathia, the uvula touching the posterior pharyngeal wall in the supine position, and a 75% or more collapse at the soft palate during the Muller maneuver were all significant predictors of sleep apnea in women with a body mass index (BMI) 2 but not in overweight women. [ABSTRACT FROM AUTHOR]

The study of atmospheric emissions from orbit to probe the middle and upper atmosphere of Mars, which started with the Mariner missions, is living a golden era thanks to the European Space Agency (ESA) Mars Express mission and other subsequent missions built upon its success, including the ESA ExoMars Trace Gas Orbiter (TGO) mission. Here we summarize the most relevant information obtained by the analysis of atmospheric emissions data from Mars Express and TGO, about the temperature and density structure, the atmospheric dynamics, the chemistry and the atmospheric escape to space. Mars Express also opened a new field of research on Mars with the discovery of aurorae on the planet. We present here the most outstanding results collected by Mars Express about aurorae. Finally, we also discuss how later measurements by other missions have complemented Mars Express and TGO results, and the potential future developments relevant to this field of research. [ABSTRACT FROM AUTHOR]

Purpose: Automated treatment planning strategies are being widely implemented in clinical routines to reduce inter‐planner variability, speed up the optimization process, and improve plan quality. This study aims to evaluate the feasibility and quality of intensity‐modulated proton therapy (IMPT) plans generated with four different knowledge‐based planning (KBP) pipelines fully integrated into a commercial treatment planning system (TPS). Materials/Methods: A data set containing 60 oropharyngeal cancer patients was split into 11 folds, each containing 47 patients for training, five patients for validation, and five patients for testing. A dose prediction model was trained on each of the folds, resulting in a total of 11 models. Three patients were left out in order to assess if the differences introduced between models were significant. From voxel‐based dose predictions, we analyze the two steps that follow the dose prediction: post‐processing of the predicted dose and dose mimicking (DM). We focused on the effect of post‐processing (PP) or no post‐processing (NPP) combined with two different DM algorithms for optimization: the one available in the commercial TPS RayStation (RSM) and a simpler isodose‐based mimicking (IBM). Using 55 test patients (five test patients for each model), we evaluated the quality and robustness of the plans generated by the four proposed KBP pipelines (PP‐RSM, PP‐IBM, NPP‐RSM, NPP‐IBM). After robust evaluation, dose‐volume histogram (DVH) metrics in nominal and worst‐case scenarios were compared to those of the manually generated plans. Results: Nominal doses from the four KBP pipelines showed promising results achieving comparable target coverage and improved dose to organs at risk (OARs) compared to the manual plans. However, too optimistic post‐processing applied to the dose prediction (i.e. important decrease of the dose to the organs) compromised the robustness of the plans. Even though RSM seemed to partially compensate for the lack of robustness in the PP plans, still 65% of the patients did not achieve the expected robustness levels. NPP‐RSM plans seemed to achieve the best trade‐off between robustness and OAR sparing. Discussion/Conclusions: PP and DM strategies are crucial steps to generate acceptable robust and deliverable IMPT plans from ML‐predicted doses. Before the clinical implementation of any KBP pipeline, the PP and DM parameters predefined by the commercial TPS need to be modified accordingly with a comprehensive feedback loop in which the robustness of the final dose calculations is evaluated. With the right choice of PP and DM parameters, KBP strategies have the potential to generate IMPT plans within clinically acceptable levels comparable to plans manually generated by dosimetrists. [ABSTRACT FROM AUTHOR]

Operation of powerful satellite- and rocket-born sounding radars is often accompanied by a heating/acceleration of the local electrons and ions. On earlier missions, intense fluxes of sounder accelerated particles were detected in Earth's ionosphere when the frequency of the radar transmitter was close to one of the fundamental plasma resonances: harmonic of the electron-cyclotron frequency, plasma or upper-hybrid frequencies. Recently it was found that running a sounder in the ionosphere of the non-magnetized Mars results in the similar effects. Ion and electron sensors of the ASPERA-3 experiment (Analyzer of Space Plasma and Energetic neutral Atoms) onboard the Mars Express spacecraft discovered acceleration of the local ionospheric ions and electrons from thermal threshold energies to 100's of eV during the active sounding phase of the onboard sounder. ESA and NASA missions in development or under study to Jupiter (JUICE- JUpiter ICy moon Explorer in 2022, Europa Clipper in 2023) and to Venus (EnVision in 2032) will also carry powerful sounding radars. In this report we review mechanisms that can cause acceleration of the plasma particles during operations of the proposed sounding radars in the Jovian system and Venusian ionosphere. Using the results of previous studies and characteristics of the proposed sounding radars onboard JUICE, Europa Clipper, and EnVision we define the optimal conditions for observations of sounder accelerated particles, depending on the local conditions, such as plasma density, composition, and intensity of the magnetic field. The EnVision radar operation is expected to results in the most pronounced acceleration of ions and electrons, an effect can be used to improve the local plasma diagnostics. [ABSTRACT FROM AUTHOR]

The deep Solar Cycle (SC) 23 minimum and the modestly active SC 24 maximum have produced generally weaker solar events and heliospheric conditions. Surprisingly, on September 10, 2017 late in the declining phase of SC 24, some of the strongest solar activity erupted from active region (AR) 12673, including an X8.2-class solar flare and a fast coronal mass ejection (CME). Associated with this activity are the solar energetic particles (SEPs), which may be accelerated locally at the flare site or by the moving shock front propagating ahead of the CME. Although AR 12673 was not centrally facing Mars (it was located about 67 degrees east in heliolongitude from the Sun-to-Mars line), the solar events impacted the local space weather environment. To name a few, some of the effects include heating of the upper atmosphere by solar flare emissions, flare-related enhancements of ion and neutral densities, solar energetic particles impacting the atmosphere and surface, bright emissions of a diffuse (global) aurora, deeply penetrating interplanetary magnetic fields over the Martian dayside, and enhanced atmospheric escape rates. In this presentation we will give an overview of the observations at Mars obtained from various Mars missions, including MAVEN, MEX, and MSL. Numerical results from the Wang-Sheeley-Arge (WSA)-Enlil-cone modeling system together with observations at Earth/L1 and STEREO-A will also be presented to provide global heliospheric context of the event period. [ABSTRACT FROM AUTHOR]

Rhinitis, Allergic Rhinitis, Chronic Rhinosinusitis, Nasal Endoscopy, Rhinitis Symptom The 22 adolescents with symptoms of CRS more often had allergic rhinitis symptoms (57.1% vs 28.1%, p=0.003) asthma (25.0% vs 11.0%, p=0.047) and cough >= 3 months (13.6% vs 3.4%, p=0.008) compared to those without symptoms of CRS. Keywords: Rhinitis; Allergic Rhinitis; Chronic Rhinosinusitis; Nasal Endoscopy; Rhinitis Symptom EN Rhinitis Allergic Rhinitis Chronic Rhinosinusitis Nasal Endoscopy Rhinitis Symptom 1 1 1 03/02/21 20150627 NES 150627 Background Symptoms of chronic rhinosinusitis (CRS) is common, around 10% among adults, and has shown to be associated with reduced quality of life. [Extracted from the article]