Search

To accurately characterize the planets a star may be hosting, stellar parameters must first be well-determined. $\tau$ Ceti is a nearby solar analog and often a target for exoplanet searches. Uncertainties in the observed rotational velocities have made constraining $\tau$ Ceti's inclination difficult. For planet candidates from radial velocity (RV) observations, this leads to substantial uncertainties in the planetary masses, as only the minimum mass ($m \sin i$) can be constrained with RV. In this paper, we used new long-baseline optical interferometric data from the CHARA Array with the MIRC-X beam combiner and extreme precision spectroscopic data from the Lowell Discovery Telescope with EXPRES to improve constraints on the stellar parameters of $\tau$ Ceti. Additional archival data were obtained from a Tennessee State University Automatic Photometric Telescope and the Mount Wilson Observatory HK project. These new and archival data sets led to improved stellar parameter determinations, including a limb-darkened angular diameter of $2.019 \pm 0.012$ mas and rotation period of $46 \pm 4$ days. By combining parameters from our data sets, we obtained an estimate for the stellar inclination of $7\pm7^\circ$. This nearly-pole-on orientation has implications for the previously-reported exoplanets. An analysis of the system dynamics suggests that the planetary architecture described by Feng et al. (2017) may not retain long-term stability for low orbital inclinations. Additionally, the inclination of $\tau$ Ceti reveals a misalignment between the inclinations of the stellar rotation axis and the previously-measured debris disk rotation axis ($i_\mathrm{disk} = 35 \pm 10^\circ$)., Comment: 14 pages, 3 figures, 4 tables, 1 appendix, accepted for publication to AJ

SU Aurigae is a widely studied T Tauri star and here we present original state-of-the-art interferometric observations with better uv and baseline coverage than previous studies. We aim to investigate the characteristics of the circumstellar material around SU Aur, constrain the disk geometry, composition and inner dust rim structure. The MIRC-X instrument at CHARA is a 6 telescope optical beam combiner offering baselines up to 331 m. We undertook image reconstruction for model-independent analysis, and fitted geometric models such as Gaussian and ring distributions. Additionally, the fitting of radiative transfer models constrains the physical parameters of the disk. Image reconstruction reveals a highly inclined disk with a slight asymmetry consistent with inclination effects obscuring the inner disk rim through absorption of incident star light on the near-side and thermal re-emission/scattering of the far-side. Geometric models find that the underlying brightness distribution is best modelled as a Gaussian with a FWHM of $1.53\pm0.01 \mathrm{mas}$ at an inclination of $56.9\pm0.4^\circ$ and minor axis position angle of $55.9\pm0.5^\circ$. Radiative transfer modelling shows a flared disk with an inner radius at 0.16 au which implies a grain size of $0.14 \mathrm{\mu m}$ assuming astronomical silicates and a scale height of 9.0 au at 100 au. In agreement with literature, only the dusty disk wind successfully accounts for the NIR excess by introducing dust above the mid-plane. Our results confirm and provide better constraints than previous inner disk studies of SU Aurigae. We confirm the presence of a dusty disk wind in the cicumstellar environment, the strength of which is enhanced by a late infall event which also causes very strong misalignments between the inner and outer disks., Comment: arXiv admin note: substantial text overlap with arXiv:2111.06205, arXiv:1905.11907

Some evolved binaries, namely post-asymptotic giant branch binaries, are surrounded by stable and massive circumbinary disks similar to protoplanetary disks found around young stars. Around 10% of these disks are transition disks: they have a large inner cavity in the dust. Previous interferometric measurements and modeling have ruled out the cavity being formed by dust sublimation and suggested that the cavity is due to a massive circumbinary planet that traps the dust in the disk and produces the observed depletion of refractory elements on the surface of the post-AGB star. In this study, we test alternative scenario in which the large cavity could be due to dynamical truncation from the inner binary. We performed near-infrared interferometric observations with the CHARA Array on the archetype of such a transition disk around a post-AGB binary: AC Her. We detect the companion at ten epochs over 4 years and determine the 3-dimensional orbit using these astrometric measurements in combination with the radial velocity time series. This is the first astrometric orbit constructed for a post-AGB binary system. We derive the best-fit orbit with a semi-major axis $2.01 \pm 0.01$ mas ($2.83\pm0.08$ au), inclination $(142.9 \pm 1.1)^\circ$ and longitude of the ascending node $(155.1 \pm 1.8)^\circ$. We find that the theoretical dynamical truncation and dust sublimation radius are at least $\sim3\times$ smaller than the observed inner disk radius ($\sim21.5$ mas or 30 au). This strengthens the hypothesis that the origin of such a cavity is due to the presence of a circumbinary planet., Accepted to be published in The Astrophysical Journal

We present measurements of the interferometrically-resolved binary star system 12 Com and the single giant star 31 Com in the cluster Coma Berenices. 12 Com is a double-lined spectroscopic binary system consisting of a G7 giant and an A3 dwarf at the cluster turnoff. Using an extensive radial velocity dataset and interferometric measurements from PTI and the CHARA array, we measured masses $M_1 =2.64 \pm 0.07 M_\odot$ and $M_2 =2.10 \pm 0.03 M_\odot$. Interferometry also allows us to resolve the giant, and measure its size as $R_1 = 9.12 \pm 0.12 \pm 0.01 R_\odot$. With the measured masses and radii, we find an age of $533 \pm 41 \pm 42$ Myr. For comparison, we measure the radius of 31 Com to be $8.36 \pm 0.15 R_\odot$. Based on the photometry and radius measurements, 12 Com A is likely the most evolved bright star in the cluster, large enough to be in the red giant phase, but too small to have core helium burning. Simultaneous knowledge of 12 Com A's mass and photometry puts strong constraints on convective core overshooting during the main sequence phase, which in turn reduces systematic uncertainties in the age. Increased precision in measuring this system also improves our knowledge of the progenitor of the cluster white dwarf WD1216+260.

To accurately characterize the planets a star may be hosting, stellar parameters must first be well-determined. $τ$ Ceti is a nearby solar analog and often a target for exoplanet searches. Uncertainties in the observed rotational velocities have made constraining $τ$ Ceti's inclination difficult. For planet candidates from radial velocity (RV) observations, this leads to substantial uncertainties in the planetary masses, as only the minimum mass ($m \sin i$) can be constrained with RV. In this paper, we used new long-baseline optical interferometric data from the CHARA Array with the MIRC-X beam combiner and extreme precision spectroscopic data from the Lowell Discovery Telescope with EXPRES to improve constraints on the stellar parameters of $τ$ Ceti. Additional archival data were obtained from a Tennessee State University Automatic Photometric Telescope and the Mount Wilson Observatory HK project. These new and archival data sets led to improved stellar parameter determinations, including a limb-darkened angular diameter of $2.019 \pm 0.012$ mas and rotation period of $46 \pm 4$ days. By combining parameters from our data sets, we obtained an estimate for the stellar inclination of $7\pm7^\circ$. This nearly-pole-on orientation has implications for the previously-reported exoplanets. An analysis of the system dynamics suggests that the planetary architecture described by Feng et al. (2017) may not retain long-term stability for low orbital inclinations. Additionally, the inclination of $τ$ Ceti reveals a misalignment between the inclinations of the stellar rotation axis and the previously-measured debris disk rotation axis ($i_\mathrm{disk} = 35 \pm 10^\circ$)., 14 pages, 3 figures, 4 tables, 1 appendix, accepted for publication to AJ

We present multi-instrument observations of the disc around the Herbig~Ae star, HD~145718, employing geometric and Monte Carlo radiative transfer models to explore the disc orientation, the vertical and radial extent of the near infrared (NIR) scattering surface, and the properties of the dust in the disc surface and sublimation rim. The disc appears inclined at $67-71^{\circ}$, with position angle, PA\,$=-1.0-0.6^{\circ}$, consistent with previous estimates. The NIR scattering surface extends out to $\sim75\,$au and we infer an aspect ratio, $h_{\rm{scat}}(r)/r\sim0.24$ in $J$-band; $\sim0.22$ in $H$-band. Our GPI images and VLTI+CHARA NIR interferometry suggest that the disc surface layers are populated by grains $\gtrsim \lambda/2\pi$ in size, indicating these grains are aerodynamically supported against settling and/or the density of smaller grains is relatively low. We demonstrate that our geometric analysis provides a reasonable assessment of the height of the NIR scattering surface at the outer edge of the disc and, if the inclination can be independently constrained, has the potential to probe the flaring exponent of the scattering surface in similarly inclined ($i\gtrsim70^{\circ}$) discs. In re-evaluating HD~145718's stellar properties, we found that the object's dimming events - previously characterised as UX~Or and dipper variability - are consistent with dust occultation by grains larger, on average, than found in the ISM. This occulting dust likely originates close to the inferred dust sublimation radius at $0.17\,$au., Comment: 18 pages, 16 figures; Accepted for publication in MNRAS

Depression in the perinatal period carries a significant burden of disease and can have negative impacts on foetuses and infants of mothers suffering from the illness. Risk factors for perinatal depression are particularly high in Low- and Middle-Income Countries (LMICs), and include partner abuse, economic insecurity, HIV, unwanted pregnancy, and food insecurity. Despite the substantial burden, there is a considerable 'treatment gap' between the need for treatment and the provision of services for perinatal depression in LMICs. Task sharing using non-specialist health workers has been recommended as a costeffective means to address this treatment gap and reduce the burden on mental health specialists in public health services. Evidence has shown moderate effects of task-shared treatments on the reduction of perinatal depression, but little is known about the processes, mechanisms and elements that lead these treatments to be effective. This thesis is nested within the Africa Focus on Intervention Research for Mental Health - South Africa (AFFIRM-SA) randomised controlled trial (RCT), which aimed to test a task-shared psychological treatment for perinatal depression in Khayelitsha, a low-income township outside of Cape Town in South Africa. The aim of this thesis was to explore the mechanisms of implementation and change of this intervention through a process evaluation. Before implementation of the intervention, qualitative research was employed to explore the idioms, symptoms and perceived causes of depression particular to perinatal women living in Khayelitsha, using semistructured interviews and a framework analysis approach. This was conducted with 12 depressed and nine non-depressed pregnant women and mothers of young babies, and 13 health care providers. These idioms and symptoms were also compared with the ICD 10 and DSM-5 criteria for major depression. The research found that local idioms used to describe depression included 'stress', 'thinking too much', being sad or unhappy, and being scared. Some of the common symptoms of depression were expressed as withdrawal and not wanting to talk, crying or sadness, poor concentration, thinking too much, fear and anxiety, stress, sleep problems, headaches, and body pain. The primary causes that women attributed to these depressive symptoms were lack of support, having an unwanted pregnancy, death of a loved one, poverty, unemployment, thinking too much, coping with a new baby, and stress. These were exacerbated by the extreme risk factors the women faced in Khayelitsha such as low income levels, poverty, partner abuse, low education levels, poor housing and living conditions, and poor health care. The findings from this research were recommended for inclusion in the development of the counselling intervention manual for the RCT. Following implementation of the AFFIRM-SA RCT counselling intervention, the trial outcome assessments found non-significant effects in the reduction of depressive symptoms on the Hamilton Depression Rating scale (HDRS) at three and 12 months post-partum, but also found significant improvements on the Edinburgh Postnatal Depression Scale (EPDS) at both time points for the intervention group, compared to the control group. The process evaluation for this thesis subsequently examined mechanisms and contextual factors that may have influenced the intervention outcome. This involved reviewing the counselling manual and conducting a grounded theory analysis of a sample of the counselling session transcripts from the intervention. The review of the counselling manual found that the structure, layout, instructions and grammar in the manual may have led to some difficulties in its interpretation and use for counsellors and participants. The grounded theory analysis included 39 participants who had completed all six sessions of the intervention (totalling 234 sessions). The use of grounded theory allowed for findings to emerge which had not been prespecified before analysis. This process began with the identification of 'open codes', which was anything that 'stood out' from the data. Following this, a secondary 'axial coding' of the data then identified four themes that encompassed all of the open codes. The themes were: therapeutic breakdowns in the counselling sessions, the adverse influence of socio-economic context on therapeutic effectiveness, reported positive outcomes, and attributes given for the reported changes. In turn, these themes could be represented by one of two 'core concepts' that characterised the processes that occurred during the counselling sessions. These were deviations from the intended counselling protocol (when things fall apart), and effectiveness of the counselling sessions (when things come together). The third level of coding, termed 'selective coding', examined the potential reasons for the deviations from protocol and the mechanisms or elements behind the attributions of the reported outcomes. Possible reasons for deviations include the original context of the development of the intervention, not fully incorporating the formative research and pilot findings, the limited skill base of the counsellors, limited training and supervision, the structure and design of the intervention, ownership by the counsellors of the intervention, the role of advice in this context, and contextually related need from the participants. This also explained potential reasons for the non-significant effects of the intervention on the HDRS. In terms of the attributions that the participants gave for their outcomes of change, many of these acted as 'mechanisms' or therapeutic elements of the counselling, and these elements were similar to previous research on common or 'non-specific' elements in the therapeutic space. These elements played an important role in participants' feelings of connection and reduction of distress, despite evidence of deviations from the counselling protocol. This was in keeping with the significant effects of the intervention on the EPDS outcomes. The thesis presents two models of processes that occurred in the intervention. The first posits that the intervention did not sufficiently disrupt the mechanisms or context that creates and perpetuates depression to enable long term shifts or significant changes in clinical depressive symptoms. The second suggests that the intervention provided a sense of connection and a subsequent 'buffer' of resilience to handle every-day stressors, but that this buffer was short-term and could not provide longer-term resilience against the extreme context of poverty, unemployment, abuse and trauma. Through a process evaluation of the design and implementation of the AFFIRM-SA intervention, this thesis presents a wide range of contextual considerations and therapeutic elements relevant to designing and implementing more acceptable and responsive public mental health interventions that aim to bring about real and sustainable change for perinatal depression in South Africa and other LMICs.

OBJECTIVE To evaluate the characteristics and outcomes of HIV-infected children that have care interruptions, during which the child's health status and use of medication is unknown. DESIGN We included data on children initiating ART between 2004 and 2016 at 180���days. Children had a care interruption if they were classified as LTFU, and subsequently returned to care. Children who died within 180���days of ART start were excluded. METHODS The main outcome was all cause mortality. Two exposed groups were considered: those with a first care interruption within the first six months on ART, and those with a first care interruption after six months on ART. Adjusted hazard ratios were determined using a Cox regression model. RESULTS Among 53,674 children included, 23,437 (44%) had a care interruption, of which 10,629 (20%) had a first care interruption within six months on ART and 12,808 (24%) had a first care interruption after six months on ART. Increased mortality was associated with a care interruption within six months on ART (adjusted hazard ratio (AHR) = 1.52, 95% CI 1.12-2.04) but not with a care interruption after six months on ART (AHR = 1.05, 95% CI 0.77-1.44). CONCLUSIONS The findings suggest that strengthening retention of children in care in the early period after ART initiation is critical to improving paediatric ART outcomes.

Within the TechCare Project, a list of Precision Livestock Farming (PLF) tools, with potential for monitoring animal welfare in small ruminant production, was formulated in TechCare Countries. The opinions of stakeholders weretaken into account after consultations, following a multi-actor approach. The OPERA method was used to reach consensus between stakeholders. Overall, stakeholders’ opinions appear rather uniform. Regarding meat sheep, thehighest appreciated PLF tool was the automated weighing and low frequency identification (LF) system, followed by localisation (GPS) and 3-axial accelerometers, as well as new ultra-high-frequency (UHF) eartags and readers forseveral uses (e.g. water intake). The most suitable PLF tools selected for dairy sheep were environmental-air quality sensors (e.g. weather stations), followed by automated milk recording, LF and automatic weighing. As for dairy goats,in addition to those selected for dairy sheep, the new UHF eartags and readers were prioritized. Regardless of the production system, the most important traits of selected PLF tools were low cost and ease-of-use. Most stakeholdersalso expressed concerns on their ability to collect and handle the data generated from PLF tools for monitoring individual animals. TechCare (www.techcare-project.eu) receives funding from the European Union’s H2020 researchand innovation programme grant no. 862050.

We observe the brightest member of the Praesepe cluster, Epsilon Cancri, to precisely measure the characteristics of the stars in this binary system, en route to a new measurement of the cluster's age. We present spectroscopic radial velocity measurements and interferometric observations of the sky-projected orbit to derive the masses, which we find to be M_1/M_sun = 2.420 +/- 0.008 and M_2/M_sun = 2.226 +/- 0.004. We place limits on the color-magnitude positions of the stars by using spectroscopic and interferometric luminosity ratios while trying to reproduce the spectral energy distribution of Epsilon Cancri. We re-examine the cluster membership of stars at the bright end of the color-magnitude diagram using Gaia data and literature radial velocity information. The binary star data are consistent with an age of 637 +/- 19 Myr, as determined from MIST model isochrones. The masses and luminosities of the stars appear to select models with the most commonly used amount of convective core overshooting., Comment: 46 pages, 15 figures

Additional file 1: Supplementary Methods, Supplementary Tables 1-3,5 and Supplementary Figures.

Highly inclined protoplanetary discs provide unique perspectives on dust evolution, allowing the vertical extent of the disc to be directly assessed. Further, polarised differential imaging (PDI) of highly inclined discs can probe the size distribution of grains in the disc's surface layers due to the size-dependence of the scattering phase function. I present our analysis of our multi-instrument observations of the highly inclined protoplanetary disc around Herbig Ae star HD 145718. By comparing synthetic images to our GPI PDI observations, we show that a reasonable assessment of the height of the scattering surface can be obtained by fitting ellipses to isophotes of $Q_{\phi}$ surface brightness. Moreover, we show this method has the potential to probe the degree of flaring in the scattering surface if the inclination is sufficiently well constrained. We use the TORUS radiative transfer code to examine the grain size distribution in the scattering surface. Our models are further constrained using an SED, constructed from archival photometry, and new and archival CHARA/MIRC-X, VLTI/GRAVITY and VLTI/PIONIER near-infrared interferometry. For typical ISM prescriptions of grain size number density, we find the largest grains in the scattering surface are ~0.5 microns in size. Larger grains have likely settled closer to the disc midplane. At the inner edge of the disc, the larger settled grains shelter small grains, allowing the sublimation rim to extend down to 0.17 au. The smaller grains emerge at larger scale heights beyond ~0.40 au.

The purpose of this study was to examine the effect of a hospital-based childbirth preparation class on birth outcomes in nulliparous women (N = 222). Outcomes of expectant mothers who attended the class were compared to a matched control cohort who did not attend preparation classes. Findings revealed women in the intervention group were more likely to give birth vaginally. While trends in a positive direction occurred, no significant difference was found in the frequency of elective induction, preterm birth, or length of stay. Data were also analyzed pre COVID-19 pandemic and 14 weeks after. A shorter time between hospital arrival and birth was significant for the intervention group. In addition, a significant change in elective induction (increase) occurred in the control group.

The distortions of absorption line profiles caused by photospheric brightness variations on the surfaces of cool, main-sequence stars can mimic or overwhelm radial velocity (RV) shifts due to the presence of exoplanets. The latest generation of precision RV spectrographs aims to detect velocity amplitudes $\lesssim 10$ cm s$^{-1}$, but requires mitigation of stellar signals. Statistical techniques are being developed to differentiate between Keplerian and activity-related velocity perturbations. Two important challenges, however, are the interpretability of the stellar activity component as RV models become more sophisticated, and ensuring the lowest-amplitude Keplerian signatures are not inadvertently accounted for in flexible models of stellar activity. For the K2V exoplanet host $��$ Eridani, we separately use ground-based photometry to constrain Gaussian processes for modeling RVs and TESS photometry with a light-curve inversion algorithm to reconstruct the stellar surface. From the reconstructions of TESS photometry, we produce an activity model, which reduces the rms scatter in RVs obtained with EXPRES from 4.72 m s$^{-1}$ to 1.98 m s$^{-1}$. We present a pilot study using the CHARA Array and MIRC-X beam combiner to directly image the starspots seen in the TESS photometry. With the limited phase coverage, our spot detections are marginal with current data but a future dedicated observing campaign should allow for imaging, as well as the stellar inclination and orientation with respect to its debris disk to be definitely determined. This work shows that stellar surface maps obtained with high cadence, time-series photometric and interferometric data can provide the constraints needed to accurately reduce RV scatter., 24 pages, 12 figures, 5 tables, accepted for publication in AJ

Time series of spectroscopic, speckle-interferometric, and optical long-baseline-interferometric observations confirm that $��$ Gem is a hierarchical triple system. It consists of an inner binary composed of two B-type stars and an outer classical Be star. Several photospheric spectral lines of the inner components were disentangled, revealing two stars with very different rotational broadening ($\sim$260 and $\sim$140 kms$^{-1}$, respectively), while the photospheric lines of the Be star remain undetected. From the combined spectroscopic and astrometric orbital solution it is not possible to unambiguously cross-identify the inner astrometric components with the spectroscopic components. In the preferred solution based on modeling of the disentangled line profiles, the inner binary is composed of two stars with nearly identical masses of 3.3 M$_\odot$ and the more rapidly rotating star is the fainter one. These two stars are in a marginally elliptical orbit ($e$ = 0.06) about each other with a period of 53.8 d. The third star also has a mass of 3.3 M$_\odot$ and follows a more eccentric ($e$ = 0.24) orbit with a period of 19.1 yr. The two orbits are co-directional and, at inclinations of 79$^{\circ}$ and 76$^{\circ}$ of the inner and the outer orbit, respectively, about coplanar. No astrometric or spectroscopic evidence could be found that the Be star itself is double. The system appears dynamically stable and not subject to eccentric Lidov-Kozai oscillations. After disentangling, the spectra of the components of the inner binary do not exhibit peculiarities that would be indicative of past interactions. Motivations for a wide range of follow-up studies are suggested., accepted to ApJ

In this contribution we report on our work to increase the spectral range of the Michigan Infrared Combiner-eXeter (MIRC-X) instrument at the CHARA array to allow for dual H and J band interferometric observations. We comment on the key science drivers behind this project and the methods of characterisation and correction of instrumental birefringence and dispersion. In addition, we report on the first results from on-sky commissioning in November 2019., 9 Pages, 6 figures. Proceedings of SPIE conference

Context. FU Orionis is the archetypal FUor star, a subclass of young stellar object (YSO) that undergo rapid brightening events, often gaining 4-6 magnitudes on timescales of days. This brightening is often associated with a massive increase in accretion; one of the most ubiquitous processes in astrophysics from planets and stars to super-massive black holes. We present multi-band interferometric observations of the FU Ori circumstellar environment, including the first J-band interferometric observations of a YSO. Aims. We investigate the morphology and temperature gradient of the inner-most regions of the accretion disk around FU Orionis. We aim to characterise the heating mechanisms of the disk and comment on potential outburst triggering processes. Methods. Recent upgrades to the MIRC-X instrument at the CHARA array allowed the first dual-band J and H observations of YSOs.Using baselines up to 331 m, we present high angular resolution data of a YSO covering the near-infrared bands J, H, and K. The unprecedented spectral range of the data allows us to apply temperature gradient models to the innermost regions of FU Ori. Results. We spatially resolve the innermost astronomical unit of the disk and determine the exponent of the temperature gradient of the inner disk to $T=r^{-0.74\pm0.02}$. This agrees with theoretical work that predicts $T = r^{-0.75}$ for actively accreting, steady state disks, a value only obtainable through viscous heating within the disk. We find a disk which extends down to the stellar surface at $0.015\pm0.007$ au where the temperature is found to be $5800\pm700$ K indicating boundary layer accretion. We find a disk inclined at $32\pm4^\circ$ with a minor-axis position angle of $34\pm11^\circ$., 10 pages, 6 figures

MIRC-X (Michigan InfraRed Combiner-eXeter) is a new highly-sensitive six-telescope interferometric imager installed at the CHARA Array that provides an angular resolution equivalent of up to a 330 m diameter baseline telescope in J and H band wavelengths ($\tfrac{\lambda}{2B}\sim0.6$ milli-arcseconds). We upgraded the original MIRC (Michigan InfraRed Combiner) instrument to improve sensitivity and wavelength coverage in two phases. First, a revolutionary sub-electron noise and fast-frame rate C-RED ONE camera based on a SAPHIRA detector was installed. Second, a new-generation beam combiner was designed and commissioned to (i) maximize sensitivity, (ii) extend the wavelength coverage to J-band, and (iii) enable polarization observations. A low-latency and fast-frame rate control software enables high-efficiency observations and fringe tracking for the forthcoming instruments at CHARA Array. Since mid-2017, MIRC-X has been offered to the community and has demonstrated best-case H-band sensitivity down to 8.2 correlated magnitude. MIRC-X uses single-mode fibers to coherently combine light of six telescopes simultaneously with an image-plane combination scheme and delivers a visibility precision better than 1%, and closure phase precision better than $1^\circ$. MIRC-X aims at (i) imaging protoplanetary disks, (ii) detecting exoplanets with precise astrometry, and (iii) imaging stellar surfaces and star-spots at an unprecedented angular resolution in the near-infrared. In this paper, we present the instrument design, installation, operation, and on-sky results, and demonstrate the imaging and astrometric capability of MIRC-X on the binary system $\iota$ Peg. The purpose of this paper is to provide a solid reference for studies based on MIRC-X data and to inspire future instruments in optical interferometry., Comment: 31 pages, 29 figures, accepted for publication in The Astronomical Journal

A crucial diagnostic that can tell us about processes involved in the formation and dynamical evolutionof planetary systems is the angle between the rotation axis of a star and a planet's orbital angular momentum vector ("spin-orbit" alignment or "obliquity"). Here we present the first spin-orbit alignment measurement for a wide-separation exoplanetary system, namely on the directly-imaged planet $��$ Pictoris b. We use VLTI/GRAVITY spectro-interferometry with an astrometric accuracy of 1 $��$as (microarcsecond) in the Br$��$ photospheric absorption line to measure the photocenter displacement associated with the stellar rotation. Taking inclination constraints from astroseismology into account, we constrain the 3-dimensional orientation of the stellar spin axis and find that $��$ Pic b orbits its host star on a prograde orbit. The angular momentum vectors of the stellar photosphere, the planet, and the outer debris disk are well-aligned with mutual inclinations $, 6 pages, 4 figures, accepted for ApJL

T Tauri stars are low-mass young stars whose disks provide the setting for planet formation. Despite this, their structure is poorly understood. We present new infrared interferometric observations of the SU Aurigae circumstellar environment that offer 3 x higher resolution and better baseline position angle coverage over previous observations. We investigate the characteristics of circumstellar material around SU Aur, constrain the disk geometry, composition and inner dust rim structure. The CHARA array offers opportunities for long baseline observations, with baselines up to 331 m. Using the CLIMB 3-telescope combiner in the K-band allows us to measure visibilities as well as closure phase. We undertook image reconstruction for model-independent analysis, and geometric modeling. Additionally, the fitting of radiative transfer models constrains the physical parameters of the disk. For the first time, a dusty disk wind is introduced to the radiative transfer code TORUS to model protoplanetary disks. Our implementation is motivated by theoretical dusty disk winds, where magnetic field lines drive dust above the disk plane close to the sublimation zone. Image reconstruction reveals an inclined disk with slight asymmetry along its minor-axis, likely due to inclination effects obscuring the inner disk rim through absorption of incident star light on the near-side and thermal re-emission/scattering of the far-side. Geometric modelling of a skewed ring finds the inner rim at 0.17+/-0.02 au with an inclination of 50.9+/-1.0 degrees and minor axis position angle 60.8+/-1.2 degrees. Radiative transfer modelling shows a flared disk with an inner radius at 0.18 au which implies a grain size of 0.4 um and a scale height of 15.0 au at 100 au. Among the tested radiative transfer models, only the dusty disk wind successfully accounts for the K-band excess by introducing dust above the mid-plane., Accepted for publication in Astronomy \& Astrophysics

There is a growing interest in the influence of vitamin D on ovine non-skeletal health. The aim of this study was to explore the relationship between pre-mating vitamin D status, as assessed by serum concentrations of 25-Hydroxyvitamin D [25(OH)D; comprising D2 and D3] and subsequent reproductive performance of genetically unimproved Scottish Blackface (UBF), genetically improved Scottish Blackface (IBF) and Lleyn ewes kept under Scottish hill conditions. 25-Hydroxyvitamin D2 (25(OH)D2) and 25-Hydroxyvitamin D3 (25(OH)D3) concentrations were determined in serum samples harvested inNovember from ewes grazed outdoors. There were no significant differences in 25(OH)D2 concentrations amongst the 3 genotypes. Lleyn ewes had significantly higher 25(OH)D3 and 25(OH)D concentrations than both Scottish Blackface ewe genotypes, whereas these vitamin D parameters did not differ significantly between the UBF and IBF ewes. Concentrations of 25(OH)D3 and 25(OH)D werepositively associated with subsequent birth weights of singleton and of twin lamb litters. No significant associations between vitamin D status and number of lambs born or weaned per ewe were found. This study demonstrates that concentrations of cutaneously-derived 25(OH)D3, but not of orally consumed25(OH)D2, differed between breeds. The positive association between ewe vitamin D status and offspring birth weight highlights the need for further investigations.

There is a growing interest in the influence of vitamin D on ovine non-skeletal health. The aim of this study was to explore the relationship between pre-mating vitamin D status, as assessed by serum concentrations of 25-Hydroxyvitamin D [25(OH)D; comprising D2 and D3] and subsequent reproductive performance of genetically unimproved Scottish Blackface (UBF), genetically improved Scottish Blackface (IBF) and Lleyn ewes kept under Scottish hill conditions. 25-Hydroxyvitamin D2 (25(OH)D2) and 25-Hydroxyvitamin D3 (25(OH)D3) concentrations were determined in serum samples harvested in November from ewes grazed outdoors. There were no significant differences in 25(OH)D2concentrations amongst the 3 genotypes. Lleyn ewes had significantly higher 25(OH)D3 and 25(OH)D concentrations than both Scottish Blackface ewe genotypes, whereas these vitamin D parameters did not differ significantly between the UBF and IBF ewes. Concentrations of 25(OH)D3 and 25(OH)D were positively associated with subsequent birth weights of singleton and of twin lamb litters. No significant associations between vitamin D status and number of lambs born or weaned per ewe were found. This study demonstrates that concentrations of cutaneously-derived 25(OH)D3, but not of orally consumed 25(OH)D2, differed between breeds. The positive association between ewe vitamin D status and offspring birth weight highlights the need for further investigations.

Supplemental material, Supplemental_Material for The development and testing of the Predictor of Appropriate Discharge Destination among patients undergoing elective total knee or hip joint arthroplasty by Charlie A Workman, Claire C Davies, Alex Lengerich, Karen C Ogle and Laura J Stark in Clinical Rehabilitation

© The Author(s) 2019., Approximately 30% of ERα breast cancer patients relapse with metastatic disease following adjuvant endocrine therapies. The connection between acquisition of drug resistance and invasive potential is poorly understood. In this study, we demonstrate that the type II keratin topological associating domain undergoes epigenetic reprogramming in aromatase inhibitors (AI)-resistant cells, leading to Keratin-80 (KRT80) upregulation. KRT80 expression is driven by de novo enhancer activation by sterol regulatory element-binding protein 1 (SREBP1). KRT80 upregulation directly promotes cytoskeletal rearrangements at the leading edge, increased focal adhesion and cellular stiffening, collectively promoting cancer cell invasion. Shearwave elasticity imaging performed on prospectively recruited patients confirms KRT80 levels correlate with stiffer tumors. Immunohistochemistry showed increased KRT80-positive cells at relapse and, using several clinical endpoints, KRT80 expression associates with poor survival. Collectively, our data uncover an unpredicted and potentially targetable direct link between epigenetic and cytoskeletal reprogramming promoting cell invasion in response to chronic AI treatment., L.M. was supported by a CRUK fellowship (C46704/A23110). Y.P. was supported by a CRUK Studentship (PS2099). A.J.F. and F.C. are funded by the Institute of Cancer Research, London (UK). F.C. is also funded by Worldwide Cancer Research (Grant 15-0273), Cancer Research UK (C57744/A22057) and the Ramon y Cajal Research Program (MINECO, RYC-2016-20352).

Low-mass, young stars — the T Tauri stars — make up the majority of young stellar objects. They have been relatively unexplored with optical long baseline interferometry owing to the cooler temperatures of their stellar photospheres which makes them fainter and more compact than the more frequently studied intermediate mass, young stars — the Herbig Ae/Be stars. With its greater flux sensitivity, GRAVITY has allowed us to explore T Tauri stars at high angular resolution in unprecedented detail. Here we present highlights from two such studies., Published in The Messenger vol. 178, pp. 43-44, December 2019.

Milliarcsecond resolution near infrared (NIR) interferometry of Herbig AeBe stars revealed a size-luminosity relation, indicating the circumstellar component arose from a dust sublimation rim, Rsub. However, evidence is mounting from e.g. NIR spectro-interferometry that optically thick material also exists interior to Rsub. Here, I present results from our comprehensive analysis of the spectral energy distribution (SED) and NIR interferometry of HD142666 using geometric and radiative transfer models. Our dataset offers the most complete uv-plane coverage obtained for a Herbig AeBe star across the NIR, featuring previously unpublished ~330m-baseline CHARA Array data, allowing us to place strong constraints on the disk viewing geometry. We find that disk models incorporating grain growth to micron-size in the inner au are required to simultaneously fit the SED and visibilities. Furthermore, models in which rim curvature arises due to the sublimation temperature's dependence on gas density better fit the data than those where curvature arises due to grain growth-induced dust settling. Contrary to prior studies, we find no direct indication of optically thick material interior to Rsub.

MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL.

We provide evidence of a pericellular network of proteases that are elevated and co-expressed in prostate cancer. The network involves the membrane bound serine proteases hepsin and TMPRSS2, the secreted kallikrein-related peptidases KLK4 and KLK14, and the secreted matrix metalloproteinases MMP-3 and MMP-9. Western blot analysis of cell lysates, conditioned cell culture media, immunoprecipitates and cell surface proteins, demonstrates a network of interactions centred largely at the plasma membrane, with the Arg/Lys specific proteases hepsin and TMPRSS2 key regulators of the network. Our data demonstrate that like TMPRSS2, hepsin is able to autoactivate. Active hepsin degrades KLK4, generating a cell associated degradation product with corresponding reduction in levels of cell-free KLK4. In contrast hepsin activates KLK14. TMPRSS2 appears to cleave amino terminal to the KLK4 activation site such that it is available for further processing to generate the active KLK4 protease. In contrast with hepsin, TMPRSS2 degrades KLK14. In addition to these direct mechanisms of regulation, hepsin and TMPRSS2 indirectly modulate KLK4 activity by cleaving the KLK4-activating protease MMP-3. Hepsin and TMPRSS2 also activate MMP-9, which similar to MMP-3, associates with the cell surface. Interestingly our data also show that proteolysis occurs between the membrane spanning and catalytic domains of hepsin and TMPRSS2. Hepsin cleavage occurs via an autoproteolytic mechanism, whereas TMPRSS2 cleavage is mediated by KLK14. Hepsin and TMPRSS2 are not shed from the cell surface but proteolysis likely disrupts domains that regulate the proteolytic activity of these proteases. Immunocytochemical analyses demonstrate that hepsin and TMPRSS2 colocalize on the cell surface with the secreted serine proteases KLK4 and KLK14, only in membrane protrusions, suggesting that reciprocal proteolytic interactions occur in defined cellular structures that are important during cancer dissemination for cell migration, invasion and survival. Also of note, immunohistochemical analysis of serial sections of prostate tumor demonstrated significant overlapping expression of the six proteases in vivo. Collectively these data suggest the possibility that the novel proteolytic network identified by us, will be most important during active dissemination of prostate cancers, and that its disruption could inhibit metastasis.

The triggering receptor expressed on myeloid cells (TREM) family of proteins are cell surface receptors with important roles in regulation of myeloid cell inflammatory activity. In the central nervous system, TREM2 is implicated in further roles in microglial homeostasis, neuroinflammation and neurodegeneration. Different TREM receptors appear to have contrasting roles in controlling myeloid immune activity therefore the relative and co-ordinated regulation of their expression is important to understand but is currently poorly understood. We sought to determine how microglial TREM expression is affected under neuroinflammatory conditions in vitro and in vivo. Our data show that microglial Trem1 and Trem2 gene expression are regulated in an opposing manner by lipopolysaccharide (LPS) in vitro in both adult murine and human microglia. LPS caused a significant induction of Trem1 and a contrasting suppression of Trem2 expression. We also observed similar divergent Trem1 and Trem2 responses in vivo in response to acute brain inflammation and acute cerebral ischaemia. Our data show that inhibition of NF-κB activation prevents the LPS-induced alterations in both Trem1 and Trem2 expression in vitro indicating NF-κB as a common signaling intermediate controlling these divergent responses. Distinct patterns of microglial Trem1 induction and Trem2 suppression to different Toll-like receptor (TLR) ligands were also evident, notably with Trem1 induction restricted to those ligands activating TLRs signaling via TRIF. Our data show co-ordinated but divergent regulation of microglial TREM receptor expression with a central role for NF-κB. Neuroinflammatory conditions that alter the balance in TREM expression could therefore be an important influence on microglial inflammatory and homeostatic activity with implications for neuroinflammatory and neurodegenerative disease.

Excessive tissue-damaging inflammation can exacerbate acute brain injury, and non-resolving inflammation is implicated in chronic neurodegeneration. Understanding the mechanisms that resolve deleterious inflammation in the brain is imperative to develop new therapeutic strategies. However current knowledge is limited, partly due to a lack of tractable models. Studies in extra-cerebral tissues have shown that myeloid cells are central to the inflammatory response. The aim of this thesis was to develop a model of self-limiting acute brain inflammation that is optimised to address mechanisms controlling resolution. The model was used to define the temporal profile of myeloid cell accumulation in the brain and establish the precise identities, origin and functional contribution of cell subsets in the resolution of the inflammatory response in the brain. Cerebral inflammation was induced by stereotaxic injection of inflammatory stimuli (LPS, HMGB1, MSU); LPS produced a robust inflammatory response and neutrophil influx and loss defined clear phases of initiation and resolution. Cellular changes (e.g. glial activation, endothelial activation and leukocyte influx) in response to LPS were characteristic of acute inflammation. Bone marrow chimaeric (Csf1r-EGFPC57Bl/6J) and monocyte reporter (Ccr2+/RFP) mice were used to distinguish between infiltrating macrophages and resident microglia. Analysis over 28 d showed the temporal profile of myeloid cells during brain inflammation, and monocyte accumulation contributed to expansion of the total mononuclear phagocyte population. Ccr2RFP/RFP knock-in mice showed that monocyte recruitment and resolution were independent of CCR2, and selective depletion of Ly6Clo monocytes with an anti- CSF1R antibody did not affect macrophage recruitment. Monocyte depletion using clodronate failed to deplete the Ly6Cint population and monocytes were still recruited into the brain. Together these results suggest multiple monocyte subsets could be involved in the inflammatory response in the brain. These data show that myeloid cell subsets of distinct origins accumulate in the inflamed brain. This work establishes a model system to identify endogenous mechanisms of resolution in cerebral inflammation and provides a platform to test CNS-targeted pro-resolution agents.

The bulk of X-ray emission from pre-main-sequence (PMS) stars is coronal in origin. We demonstrate herein that stars on Henyey tracks in the Hertzsprung-Russell diagram have lower $\log(L_X/L_\ast)$, on average, than stars on Hayashi tracks. This effect is driven by the decay of $L_X$ once stars develop radiative cores. $L_X$ decays faster with age for intermediate mass PMS stars, the progenitors of main sequence A-type stars, compared to those of lower mass. As almost all main sequence A-type stars show no detectable X-ray emission, we may already be observing the loss of their coronae during their PMS evolution. Although there is no direct link between the size or mass of the radiative core and $L_X$, the longer stars have spent with partially convective interiors, the weaker their X-ray emission becomes. This conference paper is a synopsis of Gregory, Adams and Davies (2016)., Proceedings of Cool Stars 19, Uppsala, Sweden, June 2016. 7 pages

Stars form via the gravitational collapse of molecular clouds during which time the protostellar object contracts by over seven orders of magnitude. If all the angular momentum present in the natal cloud was conserved during collapse, stars would approach rotational velocities rapid enough to tear themselves apart within just a few Myr. In contrast to this, observations of pre-main sequence rotation rates are relatively slow (∼ 1 − 15 days) indicating that significant quantities of angular momentum must be removed from the star. I use observations of fully convective pre-main sequence stars in two well-studied, nearby regions of star formation (namely the Orion Nebula Cluster and Taurus-Auriga) to determine the removal rate of stellar angular momentum. I find the accretion disc-hosting stars to be rotating at a slower rate and contain less specific angular momentum than the disc-less stars. I interpret this as indicating a period of accretion disc-regulated angular momentum evolution followed by near-constant rotational evolution following disc dispersal. Furthermore, assuming that the age spread inferred from the Hertzsprung-Russell diagram constructed for the star forming region is real, I find that the removal rate of angular momentum during the accretion-disc hosting phase to be more rapid than that expected from simple disc-locking theory whereby contraction occurs at a fixed rotation period. This indicates a more efficient process of angular momentum removal must operate, most likely in the form of an accretion-driven stellar wind or outflow emanating from the star-disc interaction. The initial circumstellar envelope that surrounds a protostellar object during the earliest stages of star formation is rotationally flattened into a disc as the star contracts. An effective viscosity, present within the disc, enables the disc to evolve: mass accretes inwards through the disc and onto the star while momentum migrates outwards, forcing the outer regions of the disc to expand. I used spatially resolved submillimetre detections of the dust and gas components of protoplanetary discs, gathered from the literature, to measure the radial extent of discs around low-mass pre-main sequence stars of ∼ 1−10 Myr and probe their viscous evolution. I find no clear observational evidence for the radial expansion of the dust component. However, I find tentative evidence for the expansion ofthe gas component. This suggests that the evolution of the gas and dust components of protoplanetary discs are likely governed by different astrophysical processes. Observations of jets and outflows emanating from protostars and pre-main sequence stars highlight that it may also be possible to remove angular momentum from the circumstellar material. Using the sample of spatially resolved protoplanetary discs, I find no evidence for angular momentum removal during disc evolution. I also use the spatially resolved debris discs from the Submillimetre Common-User Bolometer Array-2 Observations of Nearby Stars survey to constrain the amount of angular momentum retained within planetary systems. This sample is compared to the protoplanetary disc angular momenta and to the angular momentum contained within pre-stellar cores. I find that significant quantities of angular momentum must be removed during disc formation and disc dispersal. This likely occurs via magnetic braking during the formation of the disc, via the launching of a disc or photo-evaporative wind, and/or via ejection of planetary material following dynamical interactions.

This thesis adopts a socialist feminist perspective to explore women’s experiences with occupational gender segregation in unionized grocery stores across Southwestern Ontario. The thesis draws conclusions about the devaluation of women’s labour and how this devaluation impacts their economic and social status. Socialization theory and human capital theory, as well as explanations based on biology, are critiqued in this thesis, as these explanations do not fully account for occupational gender segregation. The results of this study suggest that occupational gender segregation is deeply entrenched in unionized grocery stores and the trend towards increasing profit by replacing full-time labourers with part-time labourers is further exacerbating the marginalization of women in paid labour. It is concluded that women’s labour has been steadily devalued and that class and patriarchy severally limit women’s overall upward mobility by concentrating women in highly gendered part-time low skilled jobs in grocery stores.

The immune system is implicated in a wide range of disorders affecting the brain and is, therefore, an attractive target for therapy. Interleukin-1 (IL-1) is a potent regulator of the innate immune system important for host defense but is also associated with injury and disease in the brain. Here, we show that IL-1 is a key mediator driving an innate immune response to inflammatory challenge in the mouse brain but is dispensable in extracerebral tissues including the lung and peritoneum. We also demonstrate that IL-1α is an important ligand contributing to the CNS dependence on IL-1 and that IL-1 derived from the CNS compartment (most likely microglia) is the major source driving this effect. These data reveal previously unknown tissue-specific requirements for IL-1 in driving innate immunity and suggest that IL-1-mediated inflammation in the brain could be selectively targeted without compromising systemic innate immune responses that are important for resistance to infection. This property could be exploited to mitigate injury- and disease-associated inflammation in the brain without increasing susceptibility to systemic infection, an important complication in several neurological disorders.