A review of factors influencing the utilization of eye care services

Visual impairment (low vision and blindness) is a major health concern all over the world. Three main reasons for the high prevalence of visual impairment are non-availability, non-accessibility andnon-affordability of eye care services. However, there are several factors that may act as barriers to the use of available, accessible and affordable eye care services. These include the lack of knowledge of the services, lack of knowledge of the possible impact of an eye disease and lack of knowledge of who to consult for management of eye diseases. Also, demographic, personal, social and cultural factors may influence or act as barriers to eye care utilization. These various factors are reviewed in this article. Where there is poor utilization of available services, educational campaigns would lead to better understanding and promote greater utilization of eye care services. Early detection and management of eye diseases would reduce the burden of visual impairment and disability. Therefore, eye care providers and health care managers must have good knowledge of the various factors that would negatively influence utilization of eye care services and be responsive to them. (S Afr Optom 2010 69(4) 182-193

Systematic investigation of residual strains associated with WC-Co coatings thermal sprayed onto metal substrates

Using penetrating high-energy synchrotron X-ray radiation and thermal neutrons, the residual strains and stresses associated with the high-velocity oxygen-fuel (HVOF) thermal spray coating of WC-Co on two different substrate materials with significantly different coefficients of thermal expansion (CTE) to that of the coating material, have been investigated in a systematic approach. This approach enabled quantification of the residual strain and stress contributions that emanate from the different processing steps associated with the coating process. An eigenstrain approach enabled direct comparison of the contributions of the different processing steps to the plastic strains. It is shown that the dominant contribution originates from the grit-blast surface preparation step. Contributions purely from the coating process are not distinguishable from that of the grit blasting process within the measurement accuracy. For the as-coated samples no obvious contributions ascribable to the differences in the CTEs of the substrates, or impact related effects are observed. (c) 2012 Elsevier B.V. All rights reserved

The 2016 Thermal Spray Roadmap

Considerable progress has been made over the last decades in thermal spray technologies, practices and applications. However, like other technologies, they have to continuously evolve to meet new problems and market requirements. This article aims to identify the current challenges limiting the evolution of these technologies and to propose research directions and priorities to meet these challenges. It was prepared on the basis of a collection of short articles written by experts in thermal spray who were asked to present a snapshot of the current state of their specific field, give their views on current challenges faced by the field and provide some guidance as to the R&D required to meet these challenges. The article is divided in three sections that deal with the emerging thermal spray processes, coating properties and function, and biomedical, electronic, aerospace and energy generation applications