Giant Planet Formation and Migration

© 2018, The Author(s). Planets form in circumstellar discs around young stars. Starting with sub-micron sized dust particles, giant planet formation is all about growing 14 orders of magnitude in size. It has become increasingly clear over the past decades that during all stages of giant planet formation, the building blocks are extremely mobile and can change their semimajor axis by substantial amounts. In this chapter, we aim to give a basic overview of the physical processes thought to govern giant planet formation and migration, and to highlight possible links to water delivery.S.-J. Paardekooper is supported by a Royal Society University Research Fellowship. A. Johansen is supported by the Knut and Alice Wallenberg Foundation, the Swedish Research Council (grant 2014-5775) and the European Research Council (ERC Starting Grant 278675-PEBBLE2PLANET)

A joint Fermi-GBM and Swift-BAT analysis of gravitational-wave candidates from the third gravitational-wave observing run

We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search and the Swift-BAT search, we calculate flux upper limits and present joint upper limits on the gamma-ray luminosity of each GW. Given these limits, we constrain theoretical models for the emission of gamma rays from binary black hole mergers

Constraints on the cosmic expansion history from GWTC–3

We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding ${H}_{0}={68}_{-8}^{+12}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ (68% credible interval) when combined with the H0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event's potential hosts. Assuming a fixed BBH population, we estimate a value of ${H}_{0}={68}_{-6}^{+8}\,\mathrm{km}\ \,\ {{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}$ with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H0) is the well-localized event GW190814

Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e ≤ 0.3 at 16.9 Gpc−3 yr−1 at the 90% confidence level

Pathology of uterine leiomyosarcomas and smooth muscle tumours of uncertain malignant potential

Uterine leiomyosarcomas are the most common uterine sarcomas. For clinicians, they are difficult tumours to manage. Preoperative detection is difficult because of the similarity in clinical presentation to ordinary fibroids. They are highly aggressive tumours and the effectiveness of adjuvant therapy remains controversial with surgery remaining the mainstay of treatment. Despite treatment, disease frequently recurs. For pathologists, diagnosis of most leiomyosarcomas using current diagnostic criteria is usually straightforward, as most tumours often possess two or more diagnostic microscopic features, including diffuse atypia, high mitotic count and tumour cell necrosis. Diagnostic difficulties usually relate to tumours having only one of these worrisome features, with or without other additional unusual morphologic findings. These latter tumours have been labelled as uterine smooth-muscle tumours of uncertain malignant potential. Those that are followed by a recurrence are biologically low-grade leiomyosarcomas. Epithelioid and myxoid leiomyosarcomas are less common, and their diagnostic criteria are different to tumours of usual spindle cell differentiation. In this review, we discuss the pathology of leiomyosarcomas, including an update on smooth-muscle tumours of uncertain malignant potential, with emphasis on the controversy of labelling of atypical leiomyomas. The problems with histologic diagnosis, immunohistochemical studies and molecular pathology are reviewed. © 2011 Elsevier Ltd. All rights reserved.link_to_subscribed_fulltex

Ventilator-associated lung Injury

Since its introduction into clinical practice as life-sustaining therapy in the polio epidemic, mechanical ventilation has proved to be an important tool for the treatment of the respiratory failure. One of the main reasons for a patient's admission into the intensive care unit (ICU) is to receive ventilator support [1]. According to a recent review by Esteban and co-workers [2], 66% of patients who require mechanical ventilation suffer from acute respiratory failure, including acute respiratory distress syndrome (ARDS), heart failure, pneumonia, sepsis, complications of surgery and trauma. The remaining indications include coma (15%), acute exacerbation of chronic obstructive pulmonary disease (13%) and neuromuscular disorders (5%). The aims of mechanical ventilation are primarily to decrease the work of breathing and to reverse life-threatening hypoxaemia or acute progressive respiratory acidosis. However, over the last two decades, research in a number of animal models has shown that mechanical ventilation itself can produce acute lung injury (ALI) [3]. The classical form of iatrogenic lung injury, recognised clinically for many decades, is the well-known barotrauma, defined as radiological evidence of extra-alveolar air [4]. The extraalveolar accumulation of air has several manifestations, of which the most threatening is tension pneumothorax. \ua9 2008 Springer-Verlag Italia