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Ultraviolet spectra of protoplanetary disks trace distributions of warm gas at radii where rocky planets form. We combine HST-COS observations of H2 and CO emission from 12 classical T Tauri stars to more extensively map inner disk surface layers, where gas temperature distributions allow radially stratified fluorescence from the two species. We calculate empirical emitting radii for each species under the assumption that the line widths are entirely set by Keplerian broadening, demonstrating that the CO fluorescence originates further from the stars (r ~ 20 AU) than the H2 (r ~ 0.8 AU). This is supported by 2-D radiative transfer models, which show that the peak and outer radii of the CO flux distributions generally extend further into the outer disk than the H2. These results also indicate that additional sources of LyA photons remain unaccounted for, requiring more complex models to fully reproduce the molecular gas emission. As a first step, we confirm that the morphologies of the UV-CO bands and LyA radiation fields are significantly correlated and discover that both trace the degree of dust disk evolution. The UV tracers appear to follow the same sequence of disk evolution as forbidden line emission from jets and winds, as the observed LyA profiles transition between dominant red wing and dominant blue wing shapes when the high-velocity optical emission disappears. Our results suggest a scenario where UV radiation fields, disk winds and jets, and molecular gas evolve in harmony with the dust disks throughout their lifetimes., Accepted for publication in The Astronomical Journal on 7/13/2021

The mass accretion rate is a crucial parameter for the study of the evolution of accretion discs around young low-mass stellar and substellar objects (YSOs). We revisit the case of MYLup, an object where VLT/X-Shooter data suggested a negligible mass accretion rate, and show it to be accreting on a level similar to other ClassII YSOs in Lupus based on HST observations. In our HST-COS and -STIS spectra, we find many emission lines, as well as substantial FUV continuum excess emission, which can be ascribed to active accretion. The total luminosity of the CIV 1549A doublet is 4.1$\times10^{-4}$ Lsun. Using scalings between accretion luminosity, Lacc, and CIV luminosity from the literature, we derive Lacc $\sim$2$\times10^{-1}$ Lsun, which is more than an order of magnitude higher than the upper limit estimated from the X-Shooter observations. We discuss possible reasons for the X-Shooter-HST discrepancy, the most plausible being that the low contrast between the continuum excess emission and the photospheric+chromospheric emission at optical wavelengths in MYLup hampered detection of excess emission. The luminosity of the FUV continuum and CIV lines, strong H$_{2}$ fluorescence, and a "1600 A Bump" place MYLup in the class of accreting objects with gas-rich discs. So far, MYLup is the only peculiar case in which a significant difference between the HST and X-Shooter Macc estimates exists that is not ascribable to variability. The mass accretion rate inferred from the revisited Lacc estimate is Macc $\sim$ 1( $^{+1.5}_{-0.5}$ )$\times10^{-8}$ Msun/yr. This value is consistent with the typical value derived for accreting YSOs of similar mass in Lupus and points to less clearing of the inner disc than indicated by near- and mid-infrared observations. This is confirmed by ALMA data, which show that the gaps and rings seen in the sub-millimetre are relatively shallow., Comment: 13 pager, 8 figures, two tables

The physical conditions in a variety of objects (e.g. hot exoplanets and close binaries) are fundamentally influenced by external irradiation. In static cases this leads to the development of zones of different temperatures on the ‘day‐side’. In order to combine spectra from all zones to a full visible circular disk and to obtain a 1.5D spectrum we need to calculate the weight of each patch. In the following we present the geometrical considerations and calculate the observed projected area of constant temperature in an irradiated object for specific re‐radiation angles. This allows non‐isotropic models to be used. We supply an IDL code to calculate the observed projected area for any patch given the phase and angle between surface and line of sight as well as a proper weighting for each by numerical integration. We end up with a simple approach to upgrade a 1D irradiation model to a quasi 1.5D one. This method can be applied e.g. to irradiated secondaries in close binaries.

Cardiovascular parameters increase as the fear of dental treatment increases. Recordings of pulse rate and blood pressure were used to illustrate the various situations (i.e., children willing to be treated and children unwilling to be treated).

Facultative changes in the teeth, mouth, and jaw in addition to acrogeria, acromicria, and facial erythema are found with Gottron's syndrome. Hypoplasia of the jaw, changes in the position of the teeth, or disproportional relations in the vertical dimensions of the face have been observed. These findings were also recorded in the case described here. The possibility of Gottron's syndrome should be considered if several of the above-mentioned symptoms are present.