Nonlinear Schroedinger equation for a superfluid Bose gas from weak coupling to unitarity: Study of vortices

We introduce a nonlinear Schroedinger equation to describe the dynamics of a superfluid Bose gas in the crossover from the weak-coupling regime, where $a n^{1/3}\ll 1$ with $a$ the inter-atomic s-wave scattering length and $n$ the bosonic density, to the unitarity limit, where $a\to +\infty$. We call this equation the {unitarity Schroedinger equation} (USE). The zero-temperature bulk equation of state of this USE is parametrized by the Lee-Yang-Huang low-density expansion and Jastrow calculations at unitarity. With the help of the USE we study the profiles of quantized vortices and vortex-core radius in a uniform Bose gas. We also consider quantized vortices in a Bose gas under cylindrically-symmetric harmonic confinement and study their profile and chemical potential using the USE and compare the results with those obtained from the Gross-Pitaevskii-type equations valid in the weak-coupling limit. Finally, the USE is applied to calculate the breathing modes of the confined Bose gas as a function of the scattering length.Comment: 10 pages, 15 figure

Quantification of heterogeneity in lung disease with image-based pulmonary function testing

Published: 27 July 2016Computed tomography (CT) and spirometry are the mainstays of clinical pulmonary assessment. Spirometry is effort dependent and only provides a single global measure that is insensitive for regional disease, and as such, poor for capturing the early onset of lung disease, especially patchy disease such as cystic fibrosis lung disease. CT sensitively measures change in structure associated with advanced lung disease. However, obstructions in the peripheral airways and early onset of lung stiffening are often difficult to detect. Furthermore, CT imaging poses a radiation risk, particularly for young children, and dose reduction tends to result in reduced resolution. Here, we apply a series of lung tissue motion analyses, to achieve regional pulmonary function assessment in β-ENaC-overexpressing mice, a well-established model of lung disease. The expiratory time constants of regional airflows in the segmented airway tree were quantified as a measure of regional lung function. Our results showed marked heterogeneous lung function in β-ENaC-Tg mice compared to wild-type littermate controls; identified locations of airway obstruction, and quantified regions of bimodal airway resistance demonstrating lung compensation. These results demonstrate the applicability of regional lung function derived from lung motion as an effective alternative respiratory diagnostic tool.Charlene S. Stahr, Chaminda R. Samarage, Martin Donnelley, Nigel Farrow, Kaye S. Morgan, Graeme Zosky, Richard C. Boucher, Karen K. W. Siu, Marcus A. Mall, David W. Parsons, Stephen Dubsky and Andreas Foura

Defining family business: a closer look at definitional heterogeneity

Researchers have used a myriad of different definitions in seeking to explain the heterogeneity of family firms and their unique behavior; however, no widely-accepted definition exists today. Definitional clarity in any field is essential to provide (a) the basis for the analysis of performance both spatially and temporally and (b) the foundation upon which theories, frameworks and models are developed. We provide a comprehensive analysis of prior research and identify and classify 82 definitions of family business. We then review and evaluate five key theoretical perspectives in family business to identify how these have shaped and informed the definitions employed in the field and duly explain family firm heterogeneity. Finally, we provide a conceptual diagram to inform the choice of definition in different research settings

Family involvement, family influence, and family-centered non-economic goals in small firms

Using behavioral and stakeholder theories, we suggest that family firms may have family-centered non-economic goals and that these goals could influence firm behaviors. This study extends the literature by hypothesizing that the essence of family influence partially mediates the relationship between family involvement and family firms' adoption of family-centered non-economic goals. The results using 1,060 small firms support the hypotheses. Aside from contributing to family business theory by explaining and testing mediating variables as sources of goal heterogeneity among family firms, our findings also imply that the involvement and essence approaches to defining family businesses may be hierarchically reconciled

SMALL FIRM CEOS AND OUTSIDE DIRECTORSHIPS: TENURE, DEMONSTRATION AND SYNERGY EFFECTS

We investigate the determinants of the number of outside directorships held by chief executive officers (CEOs) of small, unquoted companies. CEOs of growth-oriented firm's hold more outside directorships, as do CEOs of more complex firms. This reflects the need to acquire external resources and develop internal human capital. Synergy effects were also evident in particular industries. On balance there was little evidence of perquisite consumption and some evidence that boards do have a disciplining role. Copyright � 2008 The Author.

Coaching and guidance with patient decision aids : A review of theoretical and empirical evidence

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedCoaching and guidance are structured approaches that can be used within or alongside patient decision aids (PtDAs) to facilitate the process of decision making. Coaching is provided by an individual, and guidance is embedded within the decision support materials. The purpose of this paper is to: a) present updated definitions of the concepts “coaching” and “guidance”; b) present an updated summary of current theoretical and empirical insights into the roles played by coaching/guidance in the context of PtDAs; and c) highlight emerging issues and research opportunities in this aspect of PtDA designPeer reviewedFinal Published versio