Mesospheric Motions Over Bear Lake

Since February 1999, the Utah State University Bear Lake Observatory (41.9oN, 111.4oW) dynasonde has been configured to operate as an Imaging Doppler Interferometer (IDI). Imaging Doppler interferometry is one of a number of MF/HF radar techniques used to estimate mesospheric winds and dynamics. This paper presents results of the mesospheric (50 – 115 km) background wind, tides, and planetary waves as derived from analysis of IDI observations recorded between February 03, 1999 and February 21, 2000 at Bear Lake

Jobseekers Regime and Flexible New Deal, the Six Month Offer and Support for the Newly Unemployed evaluations: An early process study

Not availabl

Relative Astrometry of Compact Flaring Structures in Sgr A* with Polarimetric VLBI

We demonstrate that polarimetric interferometry can be used to extract precise spatial information about compact polarized flares of Sgr A*. We show that, for a faint dynamical component, a single interferometric baseline suffices to determine both its polarization and projected displacement from the quiescent intensity centroid. A second baseline enables two-dimensional reconstruction of the displacement, and additional baselines can self-calibrate using the flare, enhancing synthesis imaging of the quiescent emission. We apply this technique to simulated 1.3-mm wavelength observations of a "hot spot" embedded in a radiatively inefficient accretion disk around Sgr A*. Our results indicate that, even with current sensitivities, polarimetric interferometry with the Event Horizon Telescope can achieve ~5 microarcsecond relative astrometry of compact flaring structures near Sgr A* on timescales of minutes.Comment: 9 Pages, 4 Figures, accepted for publication in Ap

Vascular Injury After Whole Thoracic X-Ray Irradiation in the Rat

Purpose To study vascular injury after whole thoracic irradiation with single sublethal doses of X-rays in the rat and to develop markers that might predict the severity of injury. Methods and Materials Rats that received 5- or 10-Gy thorax-only irradiation and age-matched controls were studied at 3 days, 2 weeks, and 1, 2, 5, and 12 months. Several pulmonary vascular parameters were evaluated, including hemodynamics, vessel density, total lung angiotensin-converting enzyme activity, and right ventricular hypertrophy. Results By 1 month, the rats in the 10-Gy group had pulmonary vascular dropout, right ventricular hypertrophy, increased pulmonary vascular resistance, increased dry lung weights, and decreases in total lung angiotensin-converting enzyme activity, as well as pulmonary artery distensibility. In contrast, irradiation with 5 Gy resulted in only a modest increase in right ventricular weight and a reduction in lung angiotensin-converting enzyme activity. Conclusion In a previous investigation using the same model, we observed that recovery from radiation-induced attenuation of pulmonary vascular reactivity occurred. In the present study, we report that deterioration results in several vascular parameters for ≤1 year after 10 Gy, suggesting sustained remodeling of the pulmonary vasculature. Our data support clinically relevant injuries that appear in a time- and dose-related manner after exposure to relatively low radiation doses

The Impact of Community Size, Community Climate, and Victimization on the Physical and Mental Health of SGM Youth

Paceley MS, Fish JN, Thomas MMC, Goffnett J. The Impact of Community Size, Community Climate, and Victimization on the Physical and Mental Health of SGM Youth. Youth & Society. 2020;52(3):427-448. Copyright © 2020, © SAGE Publications. doi:10.1177/0044118X19856141Sexual and gender minority (SGM) youth experience high rates of victimization leading to health disparities. Community size and community climate are associated with health outcomes among SGM youth; however, we lack studies that include them as covariates alongside victimization to understand their collective impact on health. This study utilized minority stress theory to understand how community context shapes experiences of victimization and health among SGM youth. SGM youth in one Midwestern U.S. state completed an online survey (n = 201) with measures of physical health, mental health, community context, and victimization. Data were analyzed via multiple regression using a path analysis framework. Results indicate that perceived climate was associated with mental, but not physical, health; Community size was unrelated to health outcomes. Victimization mediated the association between community climate and mental health. Findings are discussed in light of current literature and implications for research and practice are shared

Interpretation and the Constraints on International Courts

This paper argues that methodologies of interpretation do not do what they promise – they do not constrain interpretation by providing neutral steps that one can follow in finding out a meaning of a text – but nevertheless do their constraining work by being part of what can be described as the legal practice

A combinatorial approach to knot recognition

This is a report on our ongoing research on a combinatorial approach to knot recognition, using coloring of knots by certain algebraic objects called quandles. The aim of the paper is to summarize the mathematical theory of knot coloring in a compact, accessible manner, and to show how to use it for computational purposes. In particular, we address how to determine colorability of a knot, and propose to use SAT solving to search for colorings. The computational complexity of the problem, both in theory and in our implementation, is discussed. In the last part, we explain how coloring can be utilized in knot recognition

On the Doppler effect for light from orbiting sources in Kerr-type metrics

A formula is derived for the combined motional and gravitational Doppler effect in general stationary axisymmetric metrics for a photon emitted parallel or antiparallel to the assumed circular orbital motion of its source. The same formula is derived from eikonal approximation and Killing vector approaches to elucidate connections between observational astronomy and modern Relativity. The formula yields expected results in the limits of a moving or stationary source in the exterior Kerr and Schwarzschild metrics and a moving source in flat space.Comment: Accepted for publication in in Monthly Notices of the Royal Astronomical Society Main Journal 1.23.15. This version has substantially shortened and clarified derivations and added content regarding applicability of the derivation