Magnetic Field Generation in Stars

Enormous progress has been made on observing stellar magnetism in stars from the main sequence through to compact objects. Recent data have thrown into sharper relief the vexed question of the origin of stellar magnetic fields, which remains one of the main unanswered questions in astrophysics. In this chapter we review recent work in this area of research. In particular, we look at the fossil field hypothesis which links magnetism in compact stars to magnetism in main sequence and pre-main sequence stars and we consider why its feasibility has now been questioned particularly in the context of highly magnetic white dwarfs. We also review the fossil versus dynamo debate in the context of neutron stars and the roles played by key physical processes such as buoyancy, helicity, and superfluid turbulence,in the generation and stability of neutron star fields. Independent information on the internal magnetic field of neutron stars will come from future gravitational wave detections. Thus we maybe at the dawn of a new era of exciting discoveries in compact star magnetism driven by the opening of a new, non-electromagnetic observational window. We also review recent advances in the theory and computation of magnetohydrodynamic turbulence as it applies to stellar magnetism and dynamo theory. These advances offer insight into the action of stellar dynamos as well as processes whichcontrol the diffusive magnetic flux transport in stars.Comment: 41 pages, 7 figures. Invited review chapter on on magnetic field generation in stars to appear in Space Science Reviews, Springe

Extent and Causes of Chesapeake Bay Warming

Coastal environments such as the Chesapeake Bay have long been impacted by eutrophication stressors resulting from human activities, and these impacts are now being compounded by global warming trends. However, there are few studies documenting long-term estuarine temperature change and the relative contributions of rivers, the atmosphere, and the ocean. In this study, Chesapeake Bay warming, since 1985, is quantified using a combination of cruise observations and model outputs, and the relative contributions to that warming are estimated via numerical sensitivity experiments with a watershed–estuarine modeling system. Throughout the Bay’s main stem, similar warming rates are found at the surface and bottom between the late 1980s and late 2010s (0.02 +/- 0.02C/year, mean +/- 1 standard error), with elevated summer rates (0.04 +/- 0.01C/year) and lower rates of winter warming (0.01 +/- 0.01C/year). Most (~85%) of this estuarine warming is driven by atmospheric effects. The secondary influence of ocean warming increases with proximity to the Bay mouth, where it accounts for more than half of summer warming in bottom waters. Sea level rise has slightly reduced summer warming, and the influence of riverine warming has been limited to the heads of tidal tributaries. Future rates of warming in Chesapeake Bay will depend not only on global atmospheric trends, but also on regional circulation patterns in mid-Atlantic waters, which are currently warming faster than the atmosphere. Supporting model data available at: https://doi.org/10.25773/c774-a36

Electron Generation and Transport using Second Harmonic Laser Pulses for Fast Ignition Laser Fusion Energy

A team of University of Alberta researchers, in collaboration with an international team of investigators, has spearheaded an experiment to study the generation and transport of MeV electrons produced by ultra-high intensity second harmonic Nd:Glass laser pulses. Intensities of up to 5 x I O’ 9 W cm2 have been used to irradiate a variety of targets to investigate the conversion efficiency into MeV energy electrons, as well as the energy spectrum and angular divergence of such electrons. Their transport through a cone tip simulating the generation of an energetic electron beam for the fast ignition of a laser-compressed fuel core was also measured. The experiments were carried out at the Titan high intensity 1aser facility located at the Lawrence Livermore National Laboratory. The experiment is the first step towards evaluating the potential effectiveness of using prepulse-free shorter wavelength second harmonic laser pulses as ignition sources for Fast Ignition Fusion Energy

Identifying composites of famous faces: Investigating memory, language and system issues

Previous research on composite systems has cast doubt on their potential to produce a good likeness. Poor memory of the target's face and problems in translating a verbal description into a visual mental image were examined as possible reasons for this. A computerized composite system was used to construct facial images of famous individuals. Results indicated that a reasonable number of composites were identified overall. Composites produced directly by the “operators” tended to be more accurate than those produced via “describers”. In addition, composites produced via describers, but not those directly by operators, were less accurate when created from memory than when a photograph was provided. This suggests that verbal descriptions, as well as facial memory, may limit composite accuracy

Medication use and potentially high-risk prescribing in older patients hospitalized for diabetes: a missed opportunity to improve care?

To examine the appropriateness of medicine use and potentially high-risk prescribing before and after hospitalization for diabetes.A retrospective cohort study of patients hospitalized for diabetes was conducted using administrative data from the Australian Government Department of Veterans' Affairs for the period between 1 January 2012 and 31 December 2012. The appropriateness of medicine use and potentially high-risk prescribing, including hyper-polypharmacy and associated treatment conflicts, were examined for the 120-day periods before and after hospitalization.A total of 876 patients were hospitalized for a diabetes-related complication. Of these, 25% were not dispensed an antidiabetic medicine 4 months before hospitalization and 25% had not had their HbA1c levels measured in the preceding 6 months. The use of antidiabetic medicines increased to 85% after hospitalization, with a 25.6% relative increase (95% CI 10.9-42.1) in the proportion of those dispensed insulin. The prevalence of high-risk prescribing before hospital admission was high; 70% had >10 medicines dispensed, a third had at least one treatment conflict and half were dispensed a potentially inappropriate medicine. The use of long-acting sulphonylureas and corticosteroids had relative decreases of 46.0% (95% CI 17.0-64.9) and 29.9% (95% CI 8.8-46.0), respectively; however, few changes in other high-risk prescribing patterns were observed after discharge.This study has identified poor medication-related care and, in particular, high-risk-prescribing in people subsequently hospitalized for diabetes. While diabetes medicine use improved after hospitalization, there was little change in potentially inappropriate medicine use, which suggests that an opportunity to improve medication use in this older vulnerable population has been missed. This article is protected by copyright. All rights reserved.G. E. Caughey, J. D. Barratt, S. Shakib, A. Kemp-Casey, E. E. Roughea

Sustainable business model innovation: The role of boundary work for multi-stakeholder alignment

This study focuses on the boundary-spanning nature of sustainable business model innovation, studying multi-stakeholder engagement and alignment. Drawing on the concept of boundary work, we explore the different types of organizational boundary changes between focal companies and their external stakeholders, investigating specifically the process of exploring, negotiating, disrupting and realigning organizational boundaries. Based on an exploratory study of nine different sustainable business model initiatives from for-profit and non-profit organizations, our analysis shows how actors involved need to find alignment at normative, instrumental and strategic dimensions in order to achieve sustainable value creation. However, complexity for alignment emerges through different understandings of value, diverging interests, division of risks and responsibilities, and existing processes and activities that limits actors’ openness to align. Mutual boundary changes are thus necessary in the process of multi-stakeholder engagement in order to enhance organizations’ understanding of value and to capture the envisioned value. This paper functions as an agenda-setting paper, presenting first insights on how the boundary work lens can advance our understanding of alignment processes between focal organizations and their external stakeholders, required for sustainable business model innovation.Marketing and Consumer Researc