387 research outputs found
Factor Structure of the Barriers to Physical Activity Scale for Youth with Visual Impairments
Youth with visual impairments (VI) often experience unique barriers to physical activity (PA) compared to their sighted peers (Armstrong et al., 2018). A psychometrically sound scale for assessing barriers to PA for youth with VI is needed to facilitate research. The purpose of this paper was to confirm the ability of the previously identified three-factor structure of the Physical Activity Barriers Questionnaire for youth with Visual Impairments (PABQ-VI) to produce scores considered to be valid and reliable (Armstrong et al., 2020; Armstrong et al., 2018) that perform equally well across age, VI severity, and gender. Our results supported the three-factor structure and that the PABQ-VI produces scores considered valid and reliable. Mean, variance, and correlation differences were found in personal, social, and environmental barriers for age and VI severity, but not gender. Researchers can use the PABQ-VI to test and evaluate ways to reduce barriers for this population
Ion-beam Assisted Sputtering of Titanium Nitride Thin Films
Titanium nitride is a material of interest for many superconducting devices
such as nanowire microwave resonators and photon detectors. Thus, controlling
the growth of TiN thin films with desirable properties is of high importance.
In previous work on niobium nitride, ion beam-assisted sputtering (IBAS)
reduced nitrogen sensitivity during deposition in tandem with an increase in
nominal critical temperature. We have deposited thin films of titanium nitride
by both, the conventional method of DC reactive magnetron sputtering and the
IBAS method and compare their superconducting critical temperatures Tc as
functions of thickness, sheet resistance, and nitrogen flow rate. We perform
electrical and structural characterizations by electric transport and X-ray
diffraction measurements. Compared to the conventional method of reactive
sputtering, the IBAS technique has demonstrated a 10% increase in nominal
critical temperature and 33% reduced sensitivity to nitrogen flow, without
noticeable variation in the lattice structure. Additionally, we explore the
behavior of superconducting Tc in ultra-thin films. Trends in films grown at
high nitrogen concentrations follow predictions of mean-field theory in
disordered films and show suppression of superconducting Tc due to geometric
effects, while nitride films grown at low nitrogen concentrations strongly
deviate from the theoretical models
Conditioned emergence: a dissipative structures approach to transformation
This paper presents a novel framework for the management of organisational transformation, defined here as a relatively rapid transition from one archetype to another. The concept of dissipative structures, from the field of complexity theory, is used to develop and explain a specific sequence of activities which underpin effective transformation. This sequence integrates selected concepts from the literatures on strategic change, organisational learning and business processes; in so doing, it introduces a degree of prescriptiveness which differentiates it from other managerial interpretations of complexity theory. Specifically, it proposes a three-stage process: first, the organisation conditions the outcome of the transformation process by articulating and reconfiguring the rules which underpin its deep structure; second, it takes steps to move from its current equilibrium and, finally, it moves into a period where positive and negative feedback loops become the focus of managerial attention. The paper argues that by managing at the level of deep structure in social systems, organisations can gain some influence over self-organising processes which are typically regarded as unpredictable in the natural sciences. However, the paper further argues that this influence is limited to archetypal features and that detailed forms and behaviours are emergent properties of the system. Two illustrative case-vignettes are presented to give an insight into the practical application of the model before conclusions are reached which speculate on the implications of this approach for strategy research
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