Extending the Globular Cluster System-Halo Mass Relation to the Lowest Galaxy Masses

High mass galaxies, with halo masses $M_{200} \ge 10^{10} M_{\odot}$, reveal a remarkable near-linear relation between their globular cluster (GC) system mass and their host galaxy halo mass. Extending this relation to the mass range of dwarf galaxies has been problematic due to the difficulty in measuring independent halo masses. Here we derive new halo masses based on stellar and HI gas kinematics for a sample of nearby dwarf galaxies with GC systems. We find that the GC system mass--halo mass relation for galaxies populated by GCs holds from halo masses of $M_{200} \sim 10^{14} M_{\odot}$ down to below $M_{200}$ $\sim 10^9 M_{\odot}$, although there is a substantial increase in scatter towards low masses. In particular, three well-studied ultra diffuse galaxies, with dwarf-like stellar masses, reveal a wide range in their GC-to-halo mass ratios. We compare our GC system--halo mass relation to the recent model of El Badry et al., finding that their fiducial model does not reproduce our data in the low mass regime. This may suggest that GC formation needs to be more efficient than assumed in their model, or it may be due to the onset of stochastic GC occupation in low mass halos. Finally, we briefly discuss the stellar mass-halo mass relation for our low mass galaxies with GCs, and we suggest some nearby dwarf galaxies for which searches for GCs may be fruitful.Comment: 16 pages, 5 figures, accepted for publication in MNRA

Foreword: Theorizing Contemporary Legal Thought

This is a co-authored foreword to a symposium in Law & Contemporary Problems titled Theorizing Contemporary Legal Thought. It includes a discussion of the background of the project, a brief summary of the articles included in the issue, and a very short statement from Desautels-Stein and Kennedy on the loss of faith indicative of Contemporary Legal Thought

Precise variational tunneling rates for anharmonic oscillator with g<0

We systematically improve the recent variational calculation of the imaginary part of the ground state energy of the quartic anharmonic oscillator. The results are extremely accurate as demonstrated by deriving, from the calculated imaginary part, all perturbation coefficients via a dispersion relation and reproducing the exact values with a relative error of less than $10^{-5}$. A comparison is also made with results of a Schr\"{o}dinger calculation based on the complex rotation method.Comment: PostScrip

The Tip of the Iceberg: Finding Patients with Heart Failure with Preserved Ejection Fraction in Primary Care

Background: Heart failure with preserved ejection fraction (HFpEF) is under-identified in primary care. Aim: The aim of this study was to determine what information is available in patients’ primary care practice records that would identify patients with HFpEF. Design and Setting: Record review in two practices in East of England. Methods: Practices completed a case report form on each patient on the heart failure register and sent anonymised echocardiography reports on patients with an ejection fraction (EF) > 50%. Reports were reviewed and data analysed using SPSS. Results: 148 patients on the HF Registers with mean age 77 + 12 years were reviewed. Fifty-three patients (36%) had possible HFpEF based on available information. These patients were older and multi-morbid, including high prevalence of overweight and obesity. Confirmation of diagnosis was not possible as recommended HFpEF diagnostic information (natriuretic peptides, echocardiogram parameters of structural heart disease and diastolic function) was widely inconsistent or absent in these patients. Conclusion: Without correct identification of HFpEF, patient management may be sub-optimal or inappropriate, and lack the needed focus on comorbidities and lifestyle that can improve patient outcomes. We have described in detail the characteristics of many of the patients who probably have HFpEF in a real-world sample, and the improvements and diagnostic information required to better identify them. Identifying more than the tip of the iceberg that is the HFpEF population will allow us to improve the quality of their management, prevent ineffective healthcare and recruit patients into research.This paper presents independent research funded by the National Institute for Health Research School for Primary Care Research (NIHR SPCR)

Project Shearwater Ground Effect UAV

The Shearwater unmanned aerial vehicle is a maritime fixed-wing drone that is designed to use ground effect force generated between the aircraft and a body of water to efficiently propel itself near the surface of a body of water. Shearwater features a virtual reality pilot interface and will act as a hybrid underwater vehicle that will eventually be able to operate both above and beneath the ocean’s surface. The Shearwater team developed existing design work to produce major subsystems that culminated in a flyable functioning prototype. An existing airframe was updated with working control surfaces tested in simulation and in practice, an electrical control system, and a working virtual reality (VR) pilot view. The Shearwater team tested a practical prototype and developed an optimized virtual reality command and control system