Toric anti-self-dual Einstein metrics via complex geometry

Using the twistor correspondence, we give a classification of toric anti-self-dual Einstein metrics: each such metric is essentially determined by an odd holomorphic function. This explains how the Einstein metrics fit into the classification of general toric anti-self-dual metrics given in an earlier paper (math.DG/0602423). The results complement the work of Calderbank-Pedersen (math.DG/0105263), who describe where the Einstein metrics appear amongst the Joyce spaces, leading to a different classification. Taking the twistor transform of our result gives a new proof of their theorem.Comment: v2. Published version. Additional references. 14 page

Identification of symptom domains in ulcerative colitis that occur frequently during flares and are responsive to changes in disease activity

<p>Abstract</p> <p>Background</p> <p>Ulcerative colitis disease activity is determined by measuring symptoms and signs. Our aim was to determine which symptom domains are frequent and responsive to change in the evaluation of disease activity, which are those defined by three criteria: 1) they occur frequently during flares; 2) they improve during effective therapy for ulcerative colitis; and 3) they resolve during remission.</p> <p>Methods</p> <p>Twenty-eight symptom domains, 16 from standard indices and 12 novel domains identified by ulcerative colitis patient focus groups, were evaluated. Sixty subjects with ulcerative colitis were surveyed, rating each symptom on the three criteria with a 100 mm Visual Analogue Scale. Frequent and responsive symptoms were defined <it>a priori </it>as those whose median Visual Analogue Scale rating for all 3 criteria was significantly greater than 50.</p> <p>Results</p> <p>Thirteen of the 28 symptom domains were identified as both frequent in ulcerative colitis flares and responsive to changes in disease activity. Seven of these 13 symptom domains were novel symptoms derived from ulcerative colitis patient focus groups including stool mucus, tenesmus, fatigue, rapid postprandial bowel movements, and inability to differentiate liquid or gas from solid stool when rectal urgency occurs. Ten of the 16 symptom domains from standard indices were either infrequent or unresponsive to changes in disease activity.</p> <p>Conclusion</p> <p>Only some of the symptoms of ulcerative colitis that are important to patients are included in standard indices, and several symptoms currently measured are not frequent or responsive to change in ulcerative colitis patients. Development of survey measures of these symptom domains could significantly improve the assessment of disease activity in ulcerative colitis.</p

A prescription for the asteroseismic surface correction

In asteroseismology, the surface effect is a disparity between the observed and the modelled oscillation frequencies. It originates from improper modelling of the surface layers in stars with solar-like oscillations. Correcting the surface effect usually requires using functions with free parameters, which are conventionally fitted to the observed frequencies. On the basis that the correction should vary smoothly across the H--R diagram, we parameterize it as a simple function of three stellar surface properties: surface gravity, effective temperature, and metallicity. We determine this function by fitting stars ranging from main-sequence dwarfs to red-giant-branch stars. The absolute amount of the surface correction increases with surface gravity, but the ratio between it and $\nu_{\rm max}$ decreases. Applying the prescription has an advantage of eliminating unrealistic surface correction, which improves parameter estimations with stellar modelling. Using two open clusters, we found that adopting the prescription can help reduce the scatter of the model-derived ages for each star in the same cluster. For an application, we provide a new revision for the $\Delta\nu$ scaling relation, using our prescription to account for the surface effect in models. The values of the correction factor, $f_{\Delta\nu}$, are up to 2\% smaller than those determined without the surface effect considered, suggesting decreases of up to 4\% in asteroseismic scaling radii and up to 8\% in asteroseismic scaling masses. This revision brings the asteroseismic properties into agreement with those determined from eclipsing binaries. Finally, the new correction factor and the stellar models with the corrected frequencies are made publicly available.Comment: 11 pages, 9 figures. Submitted to MNRAS. All comments (including on refs) are welcom

Extra-intestinal malignancies in inflammatory bowel disease: Results of the 3rd ECCO Pathogenesis Scientific Workshop (III)

AbstractThe incidence of lymphoproliferative disorders (LD) is increasing in developed countries. Patients with inflammatory bowel disease (IBD) exposed to thiopurines are at additional risk of three specific forms of LD: Epstein-Barr-Virus-related post-transplant like LD, hepato-splenic T-cell lymphoma and post-mononucleosis lymphoproliferation. The risk of the two latter forms of LD can be reduced when considering specific immunosuppressive strategies in young males. It is still unclear whether the risk of uterine cervix abnormalities is increased in IBD women, irrespective of the use of immunosuppressants. Given the excess risk demonstrated in various other contexts of immunosuppression, it is currently recommended that all women with IBD, particularly those receiving immunosuppressants, strictly adhere to a screening program of cervical surveillance and undergo vaccination against HPV, when appropriate. Patients with IBD receiving immunosuppressants are at increased risk of skin cancers. The risk of non-melanoma skin cancer is notably increased in patients receiving thiopurines. Recent data suggest that the risk of melanoma is mildly increased in patients exposed to anti-TNF therapy. All IBD patients should adhere to a program of sun protection and dermatological surveillance, whose details should take into account the other non-IBD-related risk factors

Resettlement experiences and resilience in refugee youth in Perth, Western Australia

Background: In Australia, the two major pathways of refugee entry are the United Nations High Commissioner for Refugees resettlement programme and irregular maritime arrivals (IMAs) seeking asylum. The Australian Government’s policies towards IMAs since July 2013 are controversial, uncompromising and consistently harsh, with asylum seekers held in detention centres for prolonged periods. Refugees and asylum seekers have distinct and unique stressors that make resettlement difficult. Methods: This exploratory study examines resettlement experiences for refugee youth in Western Australia using the psychosocial conceptual framework and qualitative methods. Focus group discussions and key informant interviews were undertaken with verbatim transcripts analysed using thematic analysis to identify themes. Results: Themes documented that language and its impact, and experience with education, health, and social activities, support structures provided to youth and supporting future aspirations as critical to successful resettlement. This exploratory study contributes to developing a broader understanding of the resettlement experiences of refugee youth, drawing on their current and past experiences, cultural differences and mechanisms for coping. Conclusion: Fluency in English language, especially spoken, was a facilitator of successful resettlement. Our results align with previous studies documenting that support programs are vital for successful resettlement. Although faced with immense difficulties refugee youth are resilient, want to succeed and have aspirations for the future. Strategies and recommendations suggested by refugee youth themselves could be used for developing interventions to assist successful resettlement

Spironolactone and colitis: Increased mortality in rodents and in humans

Background: Crohn's disease causes intestinal inflammation leading to intestinal fibrosis. Spironolactone is an antifibrotic medication commonly used in heart failure to reduce mortality. We examined whether spironolactone is antifibrotic in the context of intestinal inflammation. Methods: In vitro, spironolactone repressed fibrogenesis in transforming growth factor beta (TGF‐β)‐stimulated human colonic myofibroblasts. However, spironolactone therapy significantly increased mortality in two rodent models of inflammation‐induced intestinal fibrosis, suggesting spironolactone could be harmful during intestinal inflammation. Since inflammatory bowel disease (IBD) patients rarely receive spironolactone therapy, we examined whether spironolactone use was associated with mortality in a common cause of inflammatory colitis, Clostridium difficile infection (CDI). Results: Spironolactone use during CDI infection was associated with increased mortality in a retrospective cohort of 4008 inpatients (15.9% vs. 9.1%, n = 390 deaths, P < 0.0001). In patients without liver disease, the adjusted odds ratio (OR) for inpatient mortality associated with 80 mg spironolactone was 1.99 (95% confidence interval [CI]: 1.51–2.63) In contrast to the main effect of spironolactone mortality, multivariate modeling revealed a protective interaction between liver disease and spironolactone dose. The adjusted OR for mortality after CDI was 1.96 (95% CI: 1.50–2.55) for patients without liver disease on spironolactone vs. 1.28 (95% CI: 0.82–2.00) for patients with liver disease on spironolactone when compared to a reference group without liver disease or spironolactone use. Conclusions: We propose that discontinuation of spironolactone in patients without liver disease during CDI could reduce hospital mortality by 2‐fold, potentially reducing mortality from CDI by 35,000 patients annually across Europe and the U.S. (Inflamm Bowel Dis 2011;)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92045/1/21929_ftp.pd

Asteroseismology with the Roman Galactic Bulge Time-Domain Survey

Asteroseismology has transformed stellar astrophysics. Red giant asteroseismology is a prime example, with oscillation periods and amplitudes that are readily detectable with time-domain space-based telescopes. These oscillations can be used to infer masses, ages and radii for large numbers of stars, providing unique constraints on stellar populations in our galaxy. The cadence, duration, and spatial resolution of the Roman galactic bulge time-domain survey (GBTDS) are well-suited for asteroseismology and will probe an important population not studied by prior missions. We identify photometric precision as a key requirement for realizing the potential of asteroseismology with Roman. A precision of 1 mmag per 15-min cadence or better for saturated stars will enable detections of the populous red clump star population in the Galactic bulge. If the survey efficiency is better than expected, we argue for repeat observations of the same fields to improve photometric precision, or covering additional fields to expand the stellar population reach if the photometric precision for saturated stars is better than 1 mmag. Asteroseismology is relatively insensitive to the timing of the observations during the mission, and the prime red clump targets can be observed in a single 70 day campaign in any given field. Complementary stellar characterization, particularly astrometry tied to the Gaia system, will also dramatically expand the diagnostic power of asteroseismology. We also highlight synergies to Roman GBTDS exoplanet science using transits and microlensing.Comment: Roman Core Community Survey White Paper, 3 pages, 4 figure

Asteroseismology with the Roman Galactic Bulge Time-Domain Survey

Asteroseismology has transformed stellar astrophysics. Red giant asteroseismology is a prime example, with oscillation periods and amplitudes that are readily detectable with time-domain space-based telescopes. These oscillations can be used to infer masses, ages and radii for large numbers of stars, providing unique constraints on stellar populations in our galaxy. The cadence, duration, and spatial resolution of the Roman galactic bulge time-domain survey (GBTDS) are well-suited for asteroseismology and will probe an important population not studied by prior missions. We identify photometric precision as a key requirement for realizing the potential of asteroseismology with Roman. A precision of 1 mmag per 15-min cadence or better for saturated stars will enable detections of the populous red clump star population in the Galactic bulge. If the survey efficiency is better than expected, we argue for repeat observations of the same fields to improve photometric precision, or covering additional fields to expand the stellar population reach if the photometric precision for saturated stars is better than 1 mmag. Asteroseismology is relatively insensitive to the timing of the observations during the mission, and the prime red clump targets can be observed in a single 70 day campaign in any given field. Complementary stellar characterization, particularly astrometry tied to the Gaia system, will also dramatically expand the diagnostic power of asteroseismology. We also highlight synergies to Roman GBTDS exoplanet science using transits and microlensing

The K2 Galactic Archaeology Program Data Release 3: Age-abundance Patterns in C1–C8 and C10–C18

© 2022. The Author(s). Published by the American Astronomical Society. Content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. https://creativecommons.org/licenses/by/4.0/Abstract: We present the third and final data release of the K2 Galactic Archaeology Program (K2 GAP) for Campaigns C1–C8 and C10–C18. We provide asteroseismic radius and mass coefficients, κ R and κ M , for ∼19,000 red giant stars, which translate directly to radius and mass given a temperature. As such, K2 GAP DR3 represents the largest asteroseismic sample in the literature to date. K2 GAP DR3 stellar parameters are calibrated to be on an absolute parallactic scale based on Gaia DR2, with red giant branch and red clump evolutionary state classifications provided via a machine-learning approach. Combining these stellar parameters with GALAH DR3 spectroscopy, we determine asteroseismic ages with precisions of ∼20%–30% and compare age-abundance relations to Galactic chemical evolution models among both low- and high-α populations for α, light, iron-peak, and neutron-capture elements. We confirm recent indications in the literature of both increased Ba production at late Galactic times as well as significant contributions to r-process enrichment from prompt sources associated with, e.g., core-collapse supernovae. With an eye toward other Galactic archeology applications, we characterize K2 GAP DR3 uncertainties and completeness using injection tests, suggesting that K2 GAP DR3 is largely unbiased in mass/age, with uncertainties of 2.9% (stat.) ± 0.1% (syst.) and 6.7% (stat.) ± 0.3% (syst.) in κ R and κ M for red giant branch stars and 4.7% (stat.) ± 0.3% (syst.) and 11% (stat.) ± 0.9% (syst.) for red clump stars. We also identify percent-level asteroseismic systematics, which are likely related to the time baseline of the underlying data, and which therefore should be considered in TESS asteroseismic analysis.Peer reviewedFinal Published versio

Results of Antiretroviral Treatment Interruption and Intensification in Advanced Multi-Drug Resistant HIV Infection from the OPTIMA Trial

BACKGROUND: Guidance is needed on best medical management for advanced HIV disease with multidrug resistance (MDR) and limited retreatment options. We assessed two novel antiretroviral (ARV) treatment approaches in this setting. METHODS AND FINDINGS: We conducted a 2×2 factorial randomized open label controlled trial in patients with a CD4 count≤300 cells/µl who had ARV treatment (ART) failure requiring retreatment, to two options (a) re-treatment with either standard (≤4 ARVs) or intensive (≥5 ARVs) ART and b) either treatment starting immediately or after a 12-week monitored ART interruption. Primary outcome was time to developing a first AIDS-defining event (ADE) or death from any cause. Analysis was by intention to treat. From 2001 to 2006, 368 patients were randomized. At baseline, mean age was 48 years, 2% were women, median CD4 count was 106/µl, mean viral load was 4.74 log(10) copies/ml, and 59% had a prior AIDS diagnosis. Median follow-up was 4.0 years in 1249 person-years of observation. There were no statistically significant differences in the primary composite outcome of ADE or death between re-treatment options of standard versus intensive ART (hazard ratio 1.17; CI 0.86-1.59), or between immediate retreatment initiation versus interruption before re-treatment (hazard ratio 0.93; CI 0.68-1.30), or in the rate of non-HIV associated serious adverse events between re-treatment options. CONCLUSIONS: We did not observe clinical benefit or harm assessed by the primary outcome in this largest and longest trial exploring both ART interruption and intensification in advanced MDR HIV infection with poor retreatment options. TRIAL REGISTRATION: Clinicaltrials.gov NCT00050089