67 research outputs found

    Spin Testing of Superalloy Disks With Dual Grain Structure

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    This 24-month program was a joint effort between Allison Advanced Development Company (AADC), General Electric Aircraft (GEAE), and NASA Glenn Research Center (GRC). AADC led the disk and spin hardware design and analysis utilizing existing Rolls-Royce turbine disk forging tooling. Testing focused on spin testing four disks: two supplied by GEAE and two by AADC. The two AADC disks were made of Alloy 10, and each was subjected to a different heat treat process: one producing dual microstructure with coarse grain size at the rim and fine grain size at the bore and the other produced single fine grain structure throughout. The purpose of the spin tests was to provide data for evaluation of the impact of dual grain structure on disk overspeed integrity (yielding) and rotor burst criteria. The program culminated with analysis and correlation of the data to current rotor overspeed criteria and advanced criteria required for dual structure disks

    Electron beam fabrication and characterization of high- resolution magnetic force microscopy tips

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    The stray field, magnetic microstructure, and switching behavior of high‐resolution electron beam fabricated thin film tips for magnetic force microscopy (MFM) are investigated with different imaging modes in a transmission electron microscope (TEM). As the tiny smooth carbon needles covered with a thermally evaporated magnetic thin film are transparent to the electron energies used in these TEMs it is possible to observe both the external stray field emanating from the tips as well as their internal domain structure. The experiments confirm the basic features of electron beam fabricated thin film tips concluded from various MFM observations using these tips. Only a weak but highly concentrated stray field is observed emanating from the immediate apex region of the tip, consistent with their capability for high resolution. It also supports the negligible perturbation of the magnetization sample due to the tip stray field observed in MFM experiments. Investigation of the magnetization distributions within the tips, as well as preliminary magnetizing experiments, confirm a preferred single domain state of the high aspect ratio tips. To exclude artefacts of the observation techniques both nonmagnetic tips and those supporting different magnetization states are used for comparison

    Sold out? The right-to-buy, gentrification and working-class displacements in London

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    Since the 1990s, the renewal of council housing estates in London has involved widespread ‘decanting’ of resident populations to allow for demolition and redevelopment, primarily by private developers who sell the majority of new housing at market rate. This process of decanting has displaced long-term council tenants and shorter-term ‘temporary’ tenants, with many notable to return to the estate. In contrast, those leaseholders who bought under the ‘right-to-buy’ legislation introduced in the 1980s have a ‘right to remain’ by virtue of the property rights they have. Nonetheless, given the threat that their property will ultimately be subject to compulsory purchase because the redevelopment of the estate is in the ‘public interest’, these leaseholders experience similar displacement pressures to other residents. Describing these pressures, this article argues that the right-to-buy legislation offered these residents the illusion of entering a property-owning middle-class, but that they were never able to escape the labelling of council estates as stigmatised spaces which have ultimately been seized by the state and capital in a moment of ‘accumulation by dispossession’

    Moral Distress Amongst American Physician Trainees Regarding Futile Treatments at the End of Life: A Qualitative Study.

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    BACKGROUND: Ethical challenges are common in end of life care; the uncertainty of prognosis and the ethically permissible boundaries of treatment create confusion and conflict about the balance between benefits and burdens experienced by patients. OBJECTIVE: We asked physician trainees in internal medicine how they reacted and responded to ethical challenges arising in the context of perceived futile treatments at the end of life and how these challenges contribute to moral distress. DESIGN: Semi-structured in-depth qualitative interviews. PARTICIPANTS: Twenty-two internal medicine residents and fellows across three American academic medical centers. APPROACH: This study uses systematic qualitative methods of data gathering, analysis and interpretation. KEY RESULTS: Physician trainees experienced significant moral distress when they felt obligated to provide treatments at or near the end of life that they believed to be futile. Some trainees developed detached and dehumanizing attitudes towards patients as a coping mechanism, which may contribute to a loss of empathy. Successful coping strategies included formal and informal conversations with colleagues and superiors about the emotional and ethical challenges of providing care at the end of life. CONCLUSIONS: Moral distress amongst physician trainees may occur when they feel obligated to provide treatments at the end of life that they believe to be futile or harmful.This study was funded by the Health Resources and Service Administration T32 HP10025-20 Training Grant, the Gates Cambridge Scholarship, Society of General Internal Medicine Founders Grant, and the Ho-Chiang Palliative Care Research Fellowship at the Johns Hopkins School of Medicine.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s11606-015-3505-

    Can antibiotic prescriptions in respiratory tract infections be improved? A cluster-randomized educational intervention in general practice – The Prescription Peer Academic Detailing (Rx-PAD) Study [NCT00272155]

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    BACKGROUND: More than half of all antibiotic prescriptions in general practice are issued for respiratory tract infections (RTIs), despite convincing evidence that many of these infections are caused by viruses. Frequent misuse of antimicrobial agents is of great global health concern, as we face an emerging worldwide threat of bacterial antibiotic resistance. There is an increasing need to identify determinants and patterns of antibiotic prescribing, in order to identify where clinical practice can be improved. METHODS/DESIGN: Approximately 80 peer continuing medical education (CME) groups in southern Norway will be recruited to a cluster randomized trial. Participating groups will be randomized either to an intervention- or a control group. A multifaceted intervention has been tailored, where key components are educational outreach visits to the CME-groups, work-shops, audit and feedback. Prescription Peer Academic Detailers (Rx-PADs), who are trained GPs, will conduct the educational outreach visits. During these visits, evidence-based recommendations of antibiotic prescriptions for RTIs will be presented and software will be handed out for installation in participants PCs, enabling collection of prescription data. These data will subsequently be linked to corresponding data from the Norwegian Prescription Database (NorPD). Individual feedback reports will be sent all participating GPs during and one year after the intervention. Main outcomes are baseline proportion of inappropriate antibiotic prescriptions for RTIs and change in prescription patterns compared to baseline one year after the initiation of the tailored pedagogic intervention. DISCUSSION: Improvement of prescription patterns in medical practice is a challenging task. A thorough evaluation of guidelines for antibiotic treatment in RTIs may impose important benefits, whereas inappropriate prescribing entails substantial costs, as well as undesirable consequences like development of antibiotic resistance. Our hypothesis is that an educational intervention program will be effective in improving prescription patterns by reducing the total number of antibiotic prescriptions, as well as reducing the amount of broad-spectrum antibiotics, with special emphasis on macrolides

    Primary Pancreatic Burkitt’s Lymphoma: A Case Report and Review of the Literature

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    Primary pancreatic lymphoma (PPL) is of very rare occurrence as an extra nodal site of Non-Hodgkin’s lymphoma (NHL). It represents less than 1% of NHL. Out of which Burkitt lymphoma of pancreas is of a rare presentation. It usually occurs in children and presenting in adults is uncommon. The prevalence of pancreatic Burkitt lymphoma is not known as the incidence is significantly low. Clinical features of PPL are predominantly nonspecific and can become difficult with associated inflammation of pancreas. Differentiation of lymphoma to adenocarcinoma is important as chemotherapy is the main stay of treatment in lymphoma. We report a case of 68-year-old female who presented with nonspecific symptoms and was found to have obstructive jaundice secondary to pancreatic head neoplasm which was proved to be pancreatic Burkitt lymphoma which is a rare presentation
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