50 research outputs found

    Multi-layered Ruthenium-modified Bond Coats for Thermal Barrier Coatings

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    Diffusional approaches for fabrication of multi-layered Ru-modified bond coats for thermal barrier coatings have been developed via low activity chemical vapor deposition and high activity pack aluminization. Both processes yield bond coats comprising two distinct B2 layers, based on NiAl and RuAl, however, the position of these layers relative to the bond coat surface is reversed when switching processes. The structural evolution of each coating at various stages of the fabrication process has been and subsequent cyclic oxidation is presented, and the relevant interdiffusion and phase equilibria issues in are discussed. Evaluation of the oxidation behavior of these Ru-modified bond coat structures reveals that each B2 interlayer arrangement leads to the formation of α-Al 2 O 3 TGO at 1100°C, but the durability of the TGO is somewhat different and in need of further improvement in both cases

    Animals, veterinarians and the sociology of diagnosis

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    While sociologists of medicine have focused their efforts on understanding human health, illness, and medicine, veterinary medical practice has not yet caught their attention in any sustained way. In this critical review paper, we use insights from the sociology of diagnosis literature to explore veterinary practice, and aim to demonstrate the importance of animals to sociological understandings of health, illness and disease. As in human medicine, our analysis shows the importance of diagnosis in creating and maintaining the power and authority of the veterinary professional. However, we then explore how diagnosis operates as a kind of dance, where professional authority can be challenged, particularly in light of the complex ethical responsibilities and clinical interactions that result from the triad of professional/owner/animal patient. Finally, we consider diagnosis via the precept of entanglement, and raise the intriguing possibility of interspecies health relations, whereby decision-making in human healthcare may be influenced by experiences in animal healthcare, and vice-versa. In our conclusion we argue that this analysis provides opportunities to scholars researching diagnosis in human healthcare, particularly around the impact of commercial drivers; has implications for veterinary and public health practitioners; and should help animate the emerging sociology of veterinary medicine

    General practitioners’ classification of patients with medically unexplained symptoms

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    In encounters between general practitioners (GPs) and patients with medically unexplained symptoms (MUS), the negotiation of the sick role is a social process. In this process, GPs not only use traditional biomedical diagnostic tools but also rely on their own opinions and evaluations of a patient’s particular circumstances in deciding whether that patient is legitimately sick. The doctor is thus a gatekeeper of legitimacy. This article presents results from a qualitative interview study conducted in Denmark with GPs concerning their approach to patients with MUS. We employ a symbolic interaction approach that pays special attention to the external validation of the sick role, making GPs’ accounts of such patients particularly relevant. One of the article’s main findings is that GPs’ criteria for judging the legitimacy of claims by those patients that present with MUS are influenced by the extent to which GPs are able to constitute these patients as people with social problems and problematic personality traits
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