1,148 research outputs found

    What makes you not a Sikh? : a preliminary mapping of values

    Get PDF
    This study sets out to establish which Sikh values contrasted with or were shared by non-Sikh adolescents. A survey of attitude toward a variety of Sikh values was fielded in a sample of 364 non-Sikh schoolchildren aged between 13 and 15 in London. Values where attitudes were least positive concerned Sikh duties/code of conduct, festivals, rituals, prayer Gurdwara attendance, listening to scripture recitation, the amrit initiation. Sikh values empathized with by non-Sikhs concerned family pride, charity, easy access to ordination and Gurdwaras, maintaining the five Ks, seeing God in all things, abstaining from meat and alcohol and belief in the stories of Guru Nanak. Further significant differences of attitude toward Sikhism were found in comparisons by sex, age and religious affiliation. Findings are applied to teaching Sikhism to pupils of no faith adherence. The study recommends the extension of values mapping to specifically Sikh populations

    Advanced Protective Coatings for Gr-Based Nuclear Propulsion Fuel Elements

    Get PDF
    A protective coating for a graphite (Gr) containing fuel element used in a nuclear thermal propulsion system includes a first layer that is configured to resist hot hydrogen attacks. The first layer has a coefficient of thermal expansion that is higher than a coefficient of thermal expansion of the Gr containing substrate. The coating also includes a plurality of second layers located between the first layer and the substrate. The second layers are configured to mitigate the differences in coefficients of thermal expansion between the first layer and the substrate to minimize debonding and exposure of the substrate to hydrogen attack. Preferably, the protective coating can comprise an outermost first layer including zirconium carbide (ZrC), a second layer including niobium (Nb), a third layer including molybdenum (Mo), and a fourth layer including molybdenum carbide (Mo.sub.2C) located adjacent to the substrate

    Advanced Stirling Duplex Materials Assessment for Potential Venus Mission Heater Head Application

    Get PDF
    This report will address materials selection for components in a proposed Venus lander system. The lander would use active refrigeration to allow Space Science instrumentation to survive the extreme environment that exists on the surface of Venus. The refrigeration system would be powered by a Stirling engine-based system and is termed the Advanced Stirling Duplex (ASD) concept. Stirling engine power conversion in its simplest definition converts heat from radioactive decay into electricity. Detailed design decisions will require iterations between component geometries, materials selection, system output, and tolerable risk. This study reviews potential component requirements against known materials performance. A lower risk, evolutionary advance in heater head materials could be offered by nickel-base superalloy single crystals, with expected capability of approximately 1100C. However, the high temperature requirements of the Venus mission may force the selection of ceramics or refractory metals, which are more developmental in nature and may not have a well-developed database or a mature supporting technology base such as fabrication and joining methods

    In-Situ Growth of Yb2O3 Layer for Sublimation Suppression for Yb14MnSb11 Thermoelectric Material for Space Power Applications

    Get PDF
    The compound Yb14MnSb11 is a p-type thermoelectric material of interest to the National Aeronautics and Space Administration (NASA) as a candidate replacement for the state-of-the-art Si-Ge used in current radioisotope thermoelectric generators (RTGs). Ideally, the hot end of this leg would operate at 1000 C in the vacuum of space. Although Yb14MnSb11 shows the potential to double the value of the thermoelectric figure of merit (zT) over that of Si-Ge at 1000 C, it suffers from a high sublimation rate at elevated temperatures and would require a coating in order to survive the required RTG lifetime of 14 years. The purpose of the present work is to measure the sublimation rate of Yb14MnSb11 and to investigate sublimation suppression for this material. This paper reports on the sublimation rate of Yb14MnSb11 at 1000 C (approximately 3 x 10(exp -3) grams per square centimeter hour) and efforts to reduce the sublimation rate with an in situ grown Yb2O3 layer. Despite the success in forming thin, dense, continuous, and adherent oxide scales on Yb14MnSb11, the scales did not prove to be sublimation barriers

    Decompressive laparotomy for abdominal compartment syndrome

    Get PDF
    Background: The effect of decompressive laparotomy on outcomes in patients with abdominal compartment syndrome has been poorly investigated. The aim of this prospective cohort study was to describe the effect of decompressive laparotomy for abdominal compartment syndrome on organ function and outcomes. Methods: This was a prospective cohort study in adult patients who underwent decompressive laparotomy for abdominal compartment syndrome. The primary endpoints were 28-day and 1-year all-cause mortality. Changes in intra-abdominal pressure (IAP) and organ function, and laparotomy-related morbidity were secondary endpoints. Results: Thirty-three patients were included in the study (20 men). Twenty-seven patients were surgical admissions treated for abdominal conditions. The median (i.q.r.) Acute Physiology And Chronic Health Evaluation (APACHE) II score was 26 (20-32). Median IAP was 23 (21-27) mmHg before decompressive laparotomy, decreasing to 12 (9-15), 13 (8-17), 12 (9-15) and 12 (9-14) mmHg after 2, 6, 24 and 72 h. Decompressive laparotomy significantly improved oxygenation and urinary output. Survivors showed improvement in organ function scores, but non-survivors did not. Fourteen complications related to the procedure developed in eight of the 33 patients. The abdomen could be closed primarily in 18 patients. The overall 28-day mortality rate was 36 per cent (12 of 33), which increased to 55 per cent (18 patients) at 1 year. Non-survivors were no different from survivors, except that they tended to be older and on mechanical ventilation. Conclusion: Decompressive laparotomy reduced IAP and had an immediate effect on organ function. It should be considered in patients with abdominal compartment syndrome

    Consensus-based statements for the management of mitochondrial stroke-like episodes [version 1; peer review: 2 approved]

    Get PDF
    BACKGROUND: Focal-onset seizures and encephalopathy are prominent features of a stroke-like episode, which is a severe neurological manifestation associated with subtypes of mitochondrial disease. Despite more than 30 years of research, the acute treatment of stroke-like episodes remains controversial. METHODS: We used the modified Delphi process to harness the clinical expertise of a group of mitochondrial disease specialists from five European countries to produce consensus guidance for the acute management of stroke-like episodes and commonly associated complications. RESULTS: Consensus on a new definition of mitochondrial stroke-like episodes was achieved and enabled the group to develop diagnostic criteria based on clinical features, neuroimaging and/or electroencephalogram findings. Guidelines for the management of strokelike episodes were agreed with aggressive seizure management strongly recommended at the outset of stroke-like episodes. CONCLUSIONS: Our consensus statement defines stroke-like episodes in terms of an epileptic encephalopathy and we have used this to revise both diagnostic criteria and guidelines for management. A prospective, multi-centre, randomised controlled trial is required for evaluating the efficacy of any compound on modifying the trajectory of stroke-like episodes

    Effects of age, need for cognition, and affective intensity on advertising effectiveness

    Get PDF
    a b s t r a c t a r t i c l e i n f o This paper explores how individual characteristics of age, need for cognition (NFC), and affective intensity (AI) interact with each other and with advertising appeal frames (i.e., rational, positive-emotional, negativeemotional) to influence ad attitudes, involvement, and recall. The mixed design study reveals that younger adults recall emotional messages, especially negative ones, better than rational ones, but recall does not differ for older adults across appeal frames. Older adults prefer rational and positive messages to negativeemotional messages but ad attitudes do not differ among younger adults across appeal frames. Finally, age interacts with AI, but not NFC, to influence ad responsiveness. Both age and AI influence ad attitudes such that older adults exhibit the most positive ad attitudes across all appeal frames

    Manifestation of ageing in the low temperature conductance of disordered insulators

    Full text link
    We are interested in the out of equilibrium phenomena observed in the electrical conductance of disordered insulators at low temperature, which may be signatures of the electron coulomb glass state. The present work is devoted to the occurrence of ageing, a benchmark phenomenon for the glassy state. It is the fact that the dynamical properties of a glass depend on its age, i.e. on the time elapsed since it was quench-cooled. We first critically analyse previous studies on disordered insulators and question their interpretation in terms of ageing. We then present new measurements on insulating granular aluminium thin films which demonstrate that the dynamics is indeed age dependent. We also show that the results of different relaxation protocols are related by a superposition principle. The implications of our findings for the mechanism of the conductance slow relaxations are then discussed

    Digital PCR methods improve detection sensitivity and measurement precision of low abundance mtDNA deletions

    Get PDF
    Mitochondrial DNA (mtDNA) mutations are a common cause of primary mitochondrial disorders, and have also been implicated in a broad collection of conditions, including aging, neurodegeneration, and cancer. Prevalent among these pathogenic variants are mtDNA deletions, which show a strong bias for the loss of sequence in the major arc between, but not including, the heavy and light strand origins of replication. Because individual mtDNA deletions can accumulate focally, occur with multiple mixed breakpoints, and in the presence of normal mtDNA sequences, methods that detect broad-spectrum mutations with enhanced sensitivity and limited costs have both research and clinical applications. In this study, we evaluated semi-quantitative and digital PCR-based methods of mtDNA deletion detection using double-stranded reference templates or biological samples. Our aim was to describe key experimental assay parameters that will enable the analysis of low levels or small differences in mtDNA deletion load during disease progression, with limited false-positive detection. We determined that the digital PCR method significantly improved mtDNA deletion detection sensitivity through absolute quantitation, improved precision and reduced assay standard error
    • …
    corecore