Control of star formation by supersonic turbulence

Understanding the formation of stars in galaxies is central to much of modern astrophysics. For several decades it has been thought that stellar birth is primarily controlled by the interplay between gravity and magnetostatic support, modulated by ambipolar diffusion. Recently, however, both observational and numerical work has begun to suggest that support by supersonic turbulence rather than magnetic fields controls star formation. In this review we outline a new theory of star formation relying on the control by turbulence. We demonstrate that although supersonic turbulence can provide global support, it nevertheless produces density enhancements that allow local collapse. Inefficient, isolated star formation is a hallmark of turbulent support, while efficient, clustered star formation occurs in its absence. The consequences of this theory are then explored for both local star formation and galactic scale star formation. (ABSTRACT ABBREVIATED)Comment: Invited review for "Reviews of Modern Physics", 87 pages including 28 figures, in pres

Customer boundary work to navigate institutional arrangements around service interactions: exploring the case of telehealth

This research extends literature on value co-creation by examining customer perspectives on institutional arrangements of service systems and how these shape customers’ efforts to navigate service interactions. Healthcare provides the empirical context for the study focusing on a digital service technology incorporated into customer interfaces. We report a qualitative inquiry carried out with 19 people with heart disease registered to a telehealth service for remote symptom monitoring. The study focuses on customer perceptions of the key differences between the healthcare system’s technological, professional and bureaucratic processes compared to family and community institutions that shape customers’ life worlds. We explain how customer perceptions shape healthcare experiences, and patterns of adaptive telehealth usage to co-create value highlighting how customers engage in boundary work. We conclude with a discussion of theoretical implications of applying boundary work to customer experience of digital interfaces within service systems