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The purpose of this study is to develop and apply clinically relevant methods of analysing the accuracy of dental appliances fabricated using additive manufacture (AM) compared to the computer-aided design (CAD) geometry. The study also compared fit between conventionally laboratory-fabricated and AM-produced base plates.

The techniques were applied to two types of dental devices where AM fabrication methods could foreseeably be used as an alternative to laboratory production. “L” and cubic shapes of defined dimensions and spatial locations were positioned on the devices which were fabricated using AM. For assessing the dimensions, the “L” and cubic shapes were then measured on the physical builds ten times and compared to the CAD model. To assess the fit of AM and lab-produced devices, three upper and three lower conventionally fabricated acrylic base plates were compared to three upper and three lower plates. Silicone impression material was allowed to set between the casts and the base plates which filled any discrepancy between the two surfaces. The thickness of this silicone media was measured ten times at five different points on each base plate type and the results compared.

The results indicated that the evaluated CAD/AM technique is able to produce dental appliance components that are consistent with tolerance levels that would be expected with conventional methods of baseplate design. This research demonstrated that a fully CAD/AM methodology represents a potentially viable alternative to conventional lab-based methods for two types of dental appliances.

This work is original. The authors do not believe any previous papers similar to the one submitted have been published.

There is a tremendous need for the valuation of small businesses. Oftentimes, small businessowners do not have the wherewithal to gather the data and keep it up to date for use in situations that require valuation. Formal valuations are necessary because they provide objective evidence of value, in contrast to value set by markets on which public companies are traded. This article focuses on some factors that impact the valuation of the business and will help small businessowners feel more comfortable talking with financial professionals about how the business might be valued.

The purpose of this research paper is to compare corrosion data obtained from additive-manufactured heat-treated (HRx) and non-heat-treated (NHRx) cobalt-chromium (Co–Cr) alloys. Heat treatments are indicated as necessary in complex intra-oral framework production by additive manufacturing to remove accumulated thermal stresses. However, heat treatments have been linked to corrosion in cast dental alloys. Currently, there are few publications on this subject for laser-sintered dental alloys required for academic review.

Five rectangular specimens (n = 5), each with a total surface area of 10.27 cm2, were fabricated for the two groups. Specimens were immersed in an artificial saliva solution suspended by a nylon thread for 42 days at 37°C. Readings for Co, Cr and molybdenum ions released into the solution were obtained using an atomic absorption spectrometer at 1-, 4-, 7-, 14-, 21-, 28-, 35- and 42-day intervals at a detection limit of one part per million. Test methods are in accordance with ISO 10271.

Results showed a higher ion release in the HRx sample, statistically significant at 99 per cent confidence level (p < 0.01). A two-way ANOVA test conducted showed that there was a main effect of day and a main effect of finish, and there was also a significant interaction between these factors.

The study concludes that, although ion release in both samples was within the safe level recommended by ISO for the three major alloying elements, heat treatment, indeed, contributed extensively to the reduced corrosion resistance in the laser-sintered Co–Cr alloy. Further biocompatibility tests are recommended.

A review of literature concerning the over‐representation of young, African‐Caribbean males within secure psychiatric services.

This paper reports on key findings from the practice survey wing of a broader knowledge review into mental health advocacy with African and Caribbean men funded by the Social Care Institute for Excellence (SCIE). Selected themes from the analysis are discussed in the light of theory regarding ethnicity, masculinity and mental health. Conclusions are drawn that suggest that understandings of mental health and advocacy within black communities are congruent with ideologies of holism, recovery and transformational goals for services and society at large. This is in contrast to experiences in mainstream mental health services which privilege a relatively narrow medical model and treatments that are emasculating. The empowerment and emancipatory potential wrapped up in both individual and collective notions of advocacy can be seen as one part of a resistance to oppressive practices and a means of reclaiming personal efficacy and potency by virtue of challenging emasculation in services.

The authors review the call for cultural competence in psychiatric diagnosis and highlight the barrier of ‘monocultural ethnocentrism’ ‐ the tendency to presume that European‐American standards fit all cultural, racial and ethnic groups. They suggest that clinicians should: familiarise themselves with the history of racism in psychiatry; avoid stereotyping; appreciate the diversity within cultural, racial and ethnic groups; understand that individuals from various cultural, racial and ethnic groups may have had more traumatic experiences; and understand that individuals from the US and UK may have experiences with racism, some of which may cause mental illness. Finally the authors suggest strategies to increase cultural competence.

Having been a promising visualization tool since 1950s, ironically, virtual reality is not widely used in the architectural design and evaluation process due to several constrains, such as the high cost of equipments and advanced programming skills required. This paper described the collaboration between design computing courses and architecture design studios that have been taught at Savannah College of Art and Design (SCAD) in 2004 and 2005. These courses explored several practical methods to integrate Low Cost Virtual Reality Aided Design (LC-VRAD) in the architectural design process. As a summary of the collaboration, this paper refers to three main aspects: (1) How to use game engine to design an affordable VR system in the ordinary studio environment. (2) How to integrate VR, into the design process, not only as a visualization tool, but also as a design instrument. (3) How to evaluate different methods of representing architectural models based on the efficiency of workflow, rendering quality and users' feedback.

Support by the Game and Interactive Design Department at SCAD, students in the School of Building Arts implemented two Low Cost VRAD methods in various design phases, starting from site analysis, schematic design, design development to the final presentation. Two popular game engines, Epic Game's Unreal engine and Director MX's Shockwave engine, were introduced to students to visualize their project in real-time. We discussed computer-aided design theories including the application of VR, as well as digital computing and human computer interaction. At the end of each quarter, feedbacks from students and faculties were collected and analyzed. These methods were revised and improved consistently across 2004 and 2005 academic year.

Examines Spain’s problems in implementing regulatory reform and offers suggestions for addressing them. Hopes to be instructive to other countries embarking on regulatory reform. Concludes that other countries should concentrate on problems on implementation that they are likely to face and should be prepared for.

This paper identifies the new economic force regenerating the East Asian economies in the post‐crisis era. Based on the convergence of five main economic indexes, it reclassifies the ten East Asian entities into four tiers, and highlights the language similarities among the tiers. It also discusses the inter‐ and intra‐regional economic dynamics, and the implications on further regional trade/investment, financial cooperation and monetary integration, such as a possible unifying Asian currency.

A parabolic trough solar collector is an advanced concentrated solar power technology that significantly captures radiant energy. Solar power will help different sectors reach their energy needs in areas where traditional fuels are in use. This study aims to examine the sensitivity analysis for optimizing the heat transfer and entropy generation in the Jeffrey magnetohydrodynamic hybrid nanofluid flow under the influence of motile gyrotactic microorganisms with solar radiation in the parabolic trough solar collectors. The influences of viscous dissipation and Ohmic heating are also considered in this investigation.

Governing partial differential equations are derived via boundary layer assumptions and nondimensionalized with the help of suitable similarity transformations. The resulting higher-order coupled ordinary differential equations are numerically investigated using the Runga-Kutta fourth-order numerical approach with the shooting technique in the computational MATLAB tool.

The numerical outcomes of influential parameters are presented graphically for velocity, temperature, entropy generation, Bejan number, drag coefficient and Nusselt number. It is observed that escalating the values of melting heat parameter and the Prandl number enhances the Nusselt number, while reverse effect is observed with an enhancement in the magnetic field parameter and bioconvection Lewis number. Increasing the magnetic field and bioconvection diffusion parameter improves the entropy and Bejan number.

Nanotechnology has captured the interest of researchers due to its engrossing performance and wide range of applications in heat transfer and solar energy storage. There are numerous advantages of hybrid nanofluids over traditional heat transfer fluids. In addition, the upswing suspension of the motile gyrotactic microorganisms improves the hybrid nanofluid stability, enhancing the performance of the solar collector. The use of solar energy reduces the industry’s dependency on fossil fuels.