Optical and UV spectroscopy of the peculiar RS CVn system, RT Lacertae

Spectra in the H-alpha and H-beta regions of the peculiar double-lined RS CVn binary, RT Lacertae, were obtained in the fall of 1984. Limited International Ultraviolet Explorer (IUE) long wavelength low and high resolution spectra were obtained concurrently. The ground based spectra have shown an asymmetry with orbital phase in the H-alpha profile. The H-beta profiles were consistent with the same effect. One hemisphere showed excess emission and the other excess absorption, with a broad Gaussian emission component superposed upon the excess H-alpha line. An improved radial velocity curve, giving a better determined mass ratio and geometry was derived. This combined with the radii implied by the rotational broadening of the spectra, showed one component to be 80 to 90% filling the equilibrium Roche surface. The two-faced nature is, therfore, very likely due to mass transfer from the contact component impacting upon its companion. Low resolution ultraviolet data showed that the supposed cooler component is bluer than its companion. High resolution ultraviolet data taken during secondary eclipse showed Mg II emission strength which decreased more slowly than the area visible. The phase behavior of the low resolution data support the former situation, indicating traditional chromospheric activity

University Classrooms as Sites of Reentry for Women and Mothers Impacted the Carceral System: An Autoethnography About Teaching, Trauma, and Healing

The United States of America is one of the leading carceral systems in the world for women. Nearly 2.2 million adults are serving time in America’s prisons and jails (BJS, 2016). Over 200,000 of these incarcerated people are women (Sentencing Project, 2018). In Illinois, 2,300 women are incarcerated in jails, most of whom are serving time for non-violent offenses like drug possession and property offenses (Sweeny, 2018). Moreover, in Illinois 8 out of 10 incarcerated women identify as mothers of children under age 18 – most of whom are the primary parent (Sweeney, 2018). Still, over 600,000 people are released from state and federal prisons annually (Carson, 2015). Of those, 81,000 women are released from state prison each year (Sentencing Project, 2018). Given that higher education access reduces recidivism, college and university classrooms are critical reentry sites for women and mothers. Utilizing an autoethnographic investigation, a qualitative research method characterized by the self as subject, this talk will draw on my memories, reflections, and dialogue pertinent to working with students, namely, women and mothers, impacted by the carceral system. Specifically, the following research questions are posed: 1) How does my identity as a state university professor inform my pedagogy with returning citizens enrolled as my student? 2) How does my identity as an African American mother inform my pedagogy when supporting the academic needs of returning citizen-mothers enrolled as my student? This autoethnography will also provide university teachers of varying academic disciplines working in a diverse context with useful tools and tips to support classroom engagement of students impacted by the carceral system. As America’s prison population is disproportionately African American and Latinx; 33% and 23%, respectively; this talk will emphasize the specific needs of students of color. Centering the unique and often marginalized experiences of Black and Brown women impacted by the carceral system, this investigation will draw on the tenets of Critical Race Theory, Intersectionality Theory, and Historical Trauma Theory. This investigation will also explore implications for college teaching and discuss best practices for the implementation of culturally responsive classroom engagement strategies used with returning citizens in the areas of: culturally responsive course readings, fostering equitable group discussions, and developing innovative course assignments that celebrate women and mother’s healing

Extremum seeking control for truck drag reduction

The aerodynamic drag on a heavy truck tractor and semi-trailer combination can be reduced by means of a wind deflector installed on the roof of the tractor cab. The drag reduction is dependent upon the height and shape of the deflector. A variable height deflector has been constructed and tested in a wind-tunnel and on-road. In this paper, an extremum-seeking control scheme is proposed to adjust on-line the deflector height to minimize the aerodynamic drag. The effectiveness of the scheme is evaluated by simulation and its practicality is evaluated

5-dimensional contact SO(3)-manifolds and Dehn twists

In this paper the 5-dimensional contact SO(3)-manifolds are classified up to equivariant contactomorphisms. The construction of such manifolds with singular orbits requires the use of generalized Dehn twists. We show as an application that all simply connected 5-manifoldswith singular orbits are realized by a Brieskorn manifold with exponents (k,2,2,2). The standard contact structure on such a manifold gives right-handed Dehn twists, and a second contact structure defined in the article gives left-handed twists.Comment: 16 pages, 1 figure; simplification of arguments by restricting classification to coorientation preserving contactomorphism

Molecfit: A general tool for telluric absorption correction. I. Method and application to ESO instruments

Context: The interaction of the light from astronomical objects with the constituents of the Earth's atmosphere leads to the formation of telluric absorption lines in ground-based collected spectra. Correcting for these lines, mostly affecting the red and infrared region of the spectrum, usually relies on observations of specific stars obtained close in time and airmass to the science targets, therefore using precious observing time. Aims: We present molecfit, a tool for correcting for telluric absorption lines based on synthetic modelling of the Earth's atmospheric transmission. Molecfit is versatile and can be used with data obtained with various ground-based telescopes and instruments. Methods: Molecfit combines a publicly available radiative transfer code, a molecular line database, atmospheric profiles, and various kernels to model the instrument line spread function. The atmospheric profiles are created by merging a standard atmospheric profile representative of a given observatory's climate, of local meteorological data, and of dynamically retrieved altitude profiles for temperature, pressure, and humidity. We discuss the various ingredients of the method, its applicability, and its limitations. We also show examples of telluric line correction on spectra obtained with a suite of ESO Very Large Telescope (VLT) instruments. Results: Compared to previous similar tools, molecfit takes the best results for temperature, pressure, and humidity in the atmosphere above the observatory into account. As a result, the standard deviation of the residuals after correction of unsaturated telluric lines is frequently better than 2% of the continuum. Conclusion: Molecfit is able to accurately model and correct for telluric lines over a broad range of wavelengths and spectral resolutions. (Abridged)Comment: 18 pages, 13 figures, 5 tables, accepted for publication in Astronomy and Astrophysic

Highly connected manifolds with positive Ricci curvature

We prove the existence of Sasakian metrics with positive Ricci curvature on certain highly connected odd dimensional manifolds. In particular, we show that manifolds homeomorphic to the 2k-fold connected sum of S^{2n-1} x S^{2n} admit Sasakian metrics with positive Ricci curvature for all k. Furthermore, a formula for computing the diffeomorphism types is given and tables are presented for dimensions 7 and 11.Comment: This is the version published by Geometry & Topology on 29 November 200

Effectiveness of the <i>Activate </i>injury prevention exercise programme to prevent injury in schoolboy rugby union

Objective The efficacious Activate injury prevention exercise programme has been shown to prevent injuries in English schoolboy rugby union. There is now a need to assess the implementation and effectiveness of Activate in the applie setting. Methods This quasi-experimental study used a 24-hour time-loss injury definition to calculate incidence (/1000 hours) and burden (days lost/1000 hours) for individuals whose teams adopted Activate (used Activate during season) versus non-adopters. The dose-response relationship of varying levels of Activate adherence (median Activate sessions per week) was also assessed. Player-level rugby exposure, sessional Activate adoption and injury reports were recorded by school gatekeepers. Rate ratios (RR), adjusted by cluster (team), were calculated using backwards stepwise Poisson regression to compare rates between adoption and adherence groups. Results Individuals in teams adopting Activate had a 23% lower match injury incidence (RR 0.77, 95% CI 0.55 to 1.07), 59% lower training injury incidence (RR 0.41, 95% CI 0.17 to 0.97) and 26% lower match injury burden (95% CI 0.46 to 1.20) than individuals on non-adopting teams. Individuals with high Activate adherence (>= 3 sessions per week) had a 67% lower training injury incidence (RR 0.33, 95% CI 0.12 to 0.91) and a 32% lower match injury incidence (RR 0.68, 95% CI 0.50 to 0.92) than individuals with low adherence (<1 session per week). While 65% of teams adopted Activate during the season, only one team used Activate three times per week, using whole phases and programme progressions. Conclusion Activate is effective at preventing injury in English schoolboy rugby. Attention should focus on factors influencing programme uptake and implementation, ensuring Activate can have maximal benefit

On Sasaki-Einstein manifolds in dimension five

We prove the existence of Sasaki-Einstein metrics on certain simply connected 5-manifolds where until now existence was unknown. All of these manifolds have non-trivial torsion classes. On several of these we show that there are a countable infinity of deformation classes of Sasaki-Einstein structures.Comment: 18 pages, Exposition was expanded and a reference adde

Spatial matter density mapping of the STAGES Abell A901/2 supercluster field with 3D lensing

We present weak lensing data from the Hubble Space Telescope(HST)/Space Telescope A901/902 Galaxy Evolution Survey (STAGES) survey to study the three-dimensional spatial distribution of matter and galaxies in the Abell 901/902 supercluster complex. Our method improves over the existing 3D lensing mapping techniques by calibrating and removing redshift bias and accounting for the effects of the radial elongation of 3D structures. We also include the first detailed noise analysis of a 3D lensing map, showing that even with deep HST-quality data, only the most massive structures, for example M200≳ 1015M⊙h-1 at z∼ 0.8, can be resolved in 3D with any reasonable redshift accuracy (Δz≈ 0.15). We compare the lensing map to the stellar mass distribution and find luminous counterparts for all mass peaks detected with a peak significance &gt;3σ. We see structures in and behind the z= 0.165 foreground supercluster, finding structure directly behind the A901b cluster at z∼ 0.6 and also behind the south-west (SW) group at z∼ 0.7. This 3D structure viewed in projection has no significant impact on recent mass estimates of A901b or the SW group components SWa and SWb. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS