662 research outputs found
PIH58 The Conceptual Framework and Content Validity of the Polycystic Ovary Syndrome Patient Reported Outcome (Pcos-Pro) Scale
Modeling magnetospheric fields in the Jupiter system
The various processes which generate magnetic fields within the Jupiter
system are exemplary for a large class of similar processes occurring at other
planets in the solar system, but also around extrasolar planets. Jupiter's
large internal dynamo magnetic field generates a gigantic magnetosphere, which
is strongly rotational driven and possesses large plasma sources located deeply
within the magnetosphere. The combination of the latter two effects is the
primary reason for Jupiter's main auroral ovals. Jupiter's moon Ganymede is the
only known moon with an intrinsic dynamo magnetic field, which generates a
mini-magnetosphere located within Jupiter's larger magnetosphere including two
auroral ovals. Ganymede's magnetosphere is qualitatively different compared to
the one from Jupiter. It possesses no bow shock but develops Alfv\'en wings
similar to most of the extrasolar planets which orbit their host stars within
0.1 AU. New numerical models of Jupiter's and Ganymede's magnetospheres
presented here provide quantitative insight into the processes that maintain
these magnetospheres. Jupiter's magnetospheric field is approximately
time-periodic at the locations of Jupiter's moons and induces secondary
magnetic fields in electrically conductive layers such as subsurface oceans. In
the case of Ganymede, these secondary magnetic fields influence the oscillation
of the location of its auroral ovals. Based on dedicated Hubble Space Telescope
observations, an analysis of the amplitudes of the auroral oscillations
provides evidence that Ganymede harbors a subsurface ocean. Callisto in
contrast does not possess a mini-magnetosphere, but still shows a perturbed
magnetic field environment. Callisto's ionosphere and atmospheric UV emission
is different compared to the other Galilean satellites as it is primarily been
generated by solar photons compared to magnetospheric electrons.Comment: Chapter for Book: Planetary Magnetis
VESS4. The Implications of False Lumen Embolization During TEVAR and EVAR on Thrombosis, Pressurization, Remodeling, and Mortality
Observations of Extreme ICME Ram Pressure Compressing Mercury's Dayside Magnetosphere to the Surface
Mercury's magnetosphere is known to be affected by enhanced ram pressures and
magnetic fields inside interplanetary coronal mass ejections (ICMEs). Here we
report detailed observations of an ICME compressing Mercury's dayside
magnetosphere to the surface. A fast CME launched from the Sun on November 29
2013 impacted first MESSENGER, which was orbiting Mercury, on November 30 and
later STEREO-A near 1 AU on December 1. Following the ICME impact, MESSENGER
remained in the solar wind as the spacecraft traveled inwards and northwards
towards Mercury's surface until it reached and passed its closest approach to
the planet (at 371 km altitude) without crossing into the magnetosphere. The
magnetospheric crossing finally occurred 1 minute before reaching the planet's
nightside at 400 km altitude and 84N latitude, indicating the lack of
dayside magnetosphere on this orbit. In addition, the peak magnetic field
measured by MESSENGER at this time was 40% above the values measured in the
orbits just prior to and after the ICME, a consequence of the magnetospheric
compression. Using both a proxy method at Mercury and measurements at STEREO-A,
we show that the extremely high ram pressure associated with this ICME was more
than high enough to collapse Mercury's weak magnetosphere. As a consequence,
the ICME plasma likely interacted with Mercury's surface, evidenced by enhanced
sodium ions in the exosphere. The collapse of Mercury's dayside magnetosphere
has important implications for the habitability of close-in exoplanets around M
dwarf stars, as such events may significantly contribute to planetary
atmospheric loss in these systems
On wind-driven electrojets at magnetic cusps in the nightside ionosphere of Mars
Mars has a complex magnetic topology where crustal magnetic fields can interact with the solar wind magnetic field to form magnetic cusps. On the nightside, solar wind electron precipitation can produce enhanced ionization at cusps while closed field regions adjacent to cusps can be devoid of significant ionization. Using an electron transport model, we calculate the spatial structure of the nightside ionosphere of Mars using Mars Global Surveyor electron measurements as input. We find that localized regions of enhanced ionospheric density can occur at magnetic cusps adjacent to low density regions. Under this configuration, thermospheric winds can drive ionospheric electrojets. Collisional ions move in the direction of the neutral winds while magnetized electrons move perpendicular to the wind direction. This difference in motion drives currents and can lead to charge accumulation at the edges of regions of enhanced ionization. Polarization fields drive secondary currents which can reinforce the primary currents leading to electrojet formation. We estimate the magnitude of these electrojets and show that their magnetic perturbations can be detectable from both orbiting spacecraft and the surface. The magnitude of the electrojets can vary on diurnal and annual time scales as the strength and direction of the winds vary. These electrojets may lead to localized Joule heating, and closure of these currents may require field-aligned currents which may play a role in high altitude acceleration processes
Realism and the wave-function
Realism -- the idea that the concepts in physical theories refer to 'things'
existing in the real world -- is introduced as a tool to analyze the status of
the wave-function. Although the physical entities are recognized by the
existence of invariant quantities, examples from classical and quantum physics
suggest that not all the theoretical terms refer to the entities: some terms
refer to properties of the entities, and some terms have only an epistemic
function. In particular, it is argued that the wave-function may be written in
terms of classical non-referring and epistemic terms. The implications for
realist interpretations of quantum mechanics and on the teaching of quantum
physics are examined.Comment: No figure
VS2. TEVAR, EVAR, Endovascular Septectomy, and Chimneys for Managing Complex Thoracoabdominal Aortic Dissection and Aneurysms
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