655 research outputs found

    Advanced Gas Turbine (AGT) Technology Development Project, ceramic component developments

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    The ceramic component technology development activity conducted by Standard Oil Engineered Materials Company while performing as a principal subcontractor to the Garrett Auxiliary Power Division for the Advanced Gas Turbine (AGT) Technology Development Project (NASA Contract DEN3-167) is summarized. The report covers the period October 1979 through July 1987, and includes information concerning ceramic technology work categorized as common and unique. The former pertains to ceramic development applicable to two parallel AGT projects established by NASA contracts DEN3-168 (AGT100) and DEN3-167 (AGT101), whereas the unique work solely pertains to Garrett directed activity under the latter contract. The AGT101 Technology Development Project is sponsored by DOE and administered by NASA-Lewis. Standard Oil directed its efforts toward the development of ceramic materials in the silicon-carbide family. Various shape forming and fabrication methods, and nondestructive evaluation techniques were explored to produce the static structural components for the ceramic engine. This permitted engine testing to proceed without program slippage

    Performance measurement of cross-culture supply chain partnership: a case study in the Chinese automotive industry

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    This study explores a performance measurement system for a dynamic supply chain partnership in a cross-cultural context. An initial framework is constructed by reviewing the existing literature, followed by an in-depth case study in the Chinese automotive industry, where the framework is refined to address the multi-cultural setting. A performance measurement, system which includes the relationship strategy and operational measurement criteria for a supply chain partnership, has been developed. The relationship strategy contains elements of strategy orientation, management style, interdependence, mutual organisational characteristics and common goals. The operational measurement criteria consist of commitment, trust, communication behaviour, information sharing, participation decision, quality, production performance, delivery, cost, supplier strength, attitude, compromise and loyalty. The last three operational measurement criteria are found to be particularly relevant to the cross-cultural feature. While existing studies tend to focus on either specific measures or individual organisations, this paper for the first time proposes a comprehensive framework to measure the performance of supply chain partnerships. The cross-cultural perspective provides a further unique view on how a performance measurement system can be responsive to the dynamics in practice

    Pulmonary Metastasectomy in Colorectal Cancer: updated analysis of 93 randomized patients - control survival is much better than previously assumed.

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    AIM: Lung metastases from colorectal cancer are resected in selected patients in the belief that this confers a significant survival advantage. It is generally assumed that the 5-year survival of these patients would be near zero without metastasectomy. We tested the clinical effectiveness of this practice in Pulmonary Metastasectomy in Colorectal Cancer (PulMiCC), a randomized, controlled noninferiority trial. METHOD: Multidisciplinary teams in 14 hospitals recruited patients with resectable lung metastases into a two-arm trial. Randomization was remote and stratified according to site, with minimization for age, sex, primary cancer stage, interval since primary resection, prior liver involvement, number of metastases and carcinoembryonic antigen level. The trial management group was blind to patient allocation until after intention-to-treat analysis. RESULTS: From 2010 to 2016, 93 participants were randomized. These patients were 35-86 years of age and had between one and six lung metastases at a median of 2.7 years after colorectal cancer resection; 29% had prior liver metastasectomy. The patient groups were well matched and the characteristics of these groups were similar to those of observational studies. The median survival after metastasectomy was 3.5 (95% CI: 3.1-6.6) years compared with 3.8 (95% CI: 3.1-4.6) years for controls. The estimated unadjusted hazard ratio for death within 5 years, comparing the metastasectomy group with the control group, was 0.93 (95% CI: 0.56-1.56). Use of chemotherapy or local ablation was infrequent and similar in each group. CONCLUSION: Patients in the control group (who did not undergo lung metastasectomy) have better survival than is assumed. Survival in the metastasectomy group is comparable with the many single-arm follow-up studies. The groups were well matched with features similar to those reported in case series

    Long Type I X-ray Bursts and Neutron Star Interior Physics

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    Superbursts are very energetic Type I X-ray bursts discovered in recent years by long term monitoring of X-ray bursters, believed to be due to unstable ignition of carbon in the deep ocean of the neutron star. A number of "intermediate duration" bursts have also been observed, probably associated with ignition of a thick helium layer. We investigate the sensitivity of these long X-ray bursts to the thermal profile of the neutron star crust and core. We first compare cooling models of superburst lightcurves with observations, and derive constraints on the ignition mass and energy release, and then calculate ignition models for superbursts and pure helium bursts, and compare to observations. The superburst lightcurves and ignition models imply that the carbon mass fraction is approximately 20% or greater in the fuel layer, constraining models of carbon production. However, the most important result is that when Cooper pairing neutrino emission is included in the crust, the temperature is too low to support unstable carbon ignition at the observed column depths. Some additional heating mechanism is required in the accumulating fuel layer to explain the observed properties of superbursts. If Cooper pair emission is less efficient than currently thought, the observed ignition depths for superbursts imply that the crust is a poor conductor, and the core neutrino emission is not more efficient than modified URCA. The observed properties of helium bursts support these conclusions, requiring inefficient crust conductivity and core neutrino emission.Comment: submitted to ApJ (22 pages, 26 figures

    How not to attack intelligent design creationism: philosophical misconceptions about methodological naturalism

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    In recent controversies about Intelligent Design Creationism (IDC), the principle of methodological naturalism (MN) has played an important role. In this paper, an often neglected distinction is made between two different conceptions of MN, each with its respective rationale and with a different view on the proper role of MN in science. According to one popular conception, MN is a self-imposed or intrinsic limitation of science, which means that science is simply not equipped to deal with claims of the supernatural (Intrinsic MN or IMN). Alternatively, we will defend MN as a provisory and empirically grounded attitude of scientists, which is justified in virtue of the consistent success of naturalistic explanations and the lack of success of supernatural explanations in the history of science (Provisory MN or PMN). Science does have a bearing on supernatural hypotheses, and its verdict is uniformly negative. We will discuss five arguments that have been proposed in support of IMN: the argument from the definition of science, the argument from lawful regularity, the science stopper argument, the argument from procedural necessity, and the testability argument. We conclude that IMN, because of its philosophical flaws, proves to be an ill-advised strategy to counter the claims of IDC. Evolutionary scientists are on firmer ground if they discard supernatural explanations on purely evidential grounds, instead of ruling them out by philosophical fiat

    Randomized Phase III Trial of Standard Therapy Plus Low Molecular Weight Heparin in Patients With Lung Cancer: FRAGMATIC Trial

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    Purpose Venous thromboembolism (VTE) is common in cancer patients. Evidence has suggested that low molecular weight heparin (LMWH) might improve survival in patients with cancer by preventing both VTE and the progression of metastases. No trial in a single cancer type has been powered to demonstrate a clinically significant survival difference. The aim of this trial was to investigate this question in patients with lung cancer. Patients and Methods We conducted a multicenter, open-label, randomized trial to evaluate the addition of a primary prophylactic dose of LMWH for 24 weeks to standard treatment in patients with newly diagnosed lung cancer of any stage and histology. The primary outcome was 1-year survival. Secondary outcomes included metastasis-free survival, VTE-free survival, toxicity, and quality of life. Results For this trial, 2,202 patients were randomly assigned to the two treatment arms over 4 years. The trial did not reach its intended number of events for the primary analysis (2,047 deaths), and data were analyzed after 2,013 deaths after discussion with the independent data monitoring committee. There was no evidence of a difference in overall or metastasis-free survival between the two arms (hazard ratio [HR], 1.01; 95% CI, 0.93 to 1.10; P = .814; and HR, 0.99; 95% CI, 0.91 to 1.08; P = .864, respectively). There was a reduction in the risk of VTE from 9.7% to 5.5% (HR, 0.57; 95% CI, 0.42 to 0.79; P = .001) in the LMWH arm and no difference in major bleeding events but evidence of an increase in the composite of major and clinically relevant nonmajor bleeding in the LMWH arm. Conclusion LMWH did not improve overall survival in the patients with lung cancer in this trial. A significant reduction in VTE is associated with an increase in clinically relevant nonmajor bleeding. Strategies to target those at greatest risk of VTE are warranted

    Tourism Partnerships in Protected Areas: Exploring Contributions to Sustainability

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    Partnerships between natural-area managers and the tourism industry have been suggested to contribute to sustainability in protected areas. This article explores how important sustainability outcomes of partnerships are to their members, how well they are realised and the features of partnerships leading to their achievement. In 21 case studies in Australia, interviews (n = 97) and surveys (n = 100) showed that of 14 sustainability outcomes, improved understanding of protected areas values and improved biodiversity conservation were the most important. Other highly ranked outcomes were greater respect for culture, heritage, and/or traditions; improved quality of environmental conditions; social benefits to local communities; and improved economic viability of the protected area. Scores for satisfaction with outcomes were, like those for importance, all high but were less than those for importance for the majority, with improvement in quality of environmental conditions showing the largest gap. The satisfaction score exceeded that for importance only for increased competitiveness of the protected area as a tourist destination. “Brown” aspects of sustainability, i.e., decreased waste or energy use, were among the lowest-scoring outcomes for both importance and satisfaction. The most important factor enabling sustainability outcomes was provision of benefits to partnership members. Others were increased financial support, inclusiveness, supportive organisational and administrative arrangements, direct involvement of decision makers, partnership maturity, creation of new relationships, decreased conflict, and stimulation of innovation. Improving sustainability outcomes, therefore, requires maintaining these partnership attributes and also increasing emphasis on reducing waste and resource use

    Antithrombotic therapy and survival in patients with malignant disease

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    A broad range of studies suggest a two-way relationship between cancer and venous thromboembolism (VTE). Patients with cancer have consistently been shown to be at elevated risk for VTE; this risk is partly driven by an intrinsic hypercoagulable state elicited by the tumour itself. Conversely, thromboembolic events in patients without obvious risk factors are often the first clinical manifestation of an undiagnosed malignancy. The relationship between VTE and cancer is further supported by a number of trials and meta-analyses which, when taken together, strongly suggest that antithrombotic therapy can extend survival in patients with cancer by a mechanism that extends beyond its effect in preventing VTE. Moreover, accumulating evidence from in vitro and in vivo studies has shown that tumour growth, invasion, and metastasis are governed, in part, by elements of the coagulation system. On 22 May 2009, a group of health-care providers based in the United Kingdom met in London, England, to examine recent advances in cancer-associated thrombosis and its implications for UK clinical practice. As part of the discussion, attendees evaluated evidence for and against an effect of antithrombotic therapy on survival in cancer. This paper includes a summary of the data presented at the meeting and explores potential mechanisms by which antithrombotic agents might exert antitumour effects. The summary is followed by a consensus statement developed by the group

    From accountability to digital data: the rise and rise of educational governance

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    Research interest in educational governance has increased in recent years with the rise to prominence of transnational organisations such as the OECD and the importance attached to international comparison of educational systems. However, rarely do educational researchers consider the historical antecedents that have attended these developments. Yet to more fully appreciate where we are now it is necessary to examine the national and global events that have shaped the current policy context. This paper presents a review of educational governance in the UK from the 1970s seeing in this a trajectory from the emergence of accountability to today’s overriding concern with digital data. In doing this, the paper aims to go beyond providing a historical account, rather its purpose is to shed light on educational change; and further, to analyse the contribution of educational research to an understanding of events as they have unfolded over the past five decades. While it is necessarily rooted within the particular historical context of the UK it can be read as an analysis of the factors influencing educational change in the context of globalised policy spaces more broadly. A recurrent theme is the appearance of the ‘unanticipated consequence’, one of the most important issues the social sciences has to contend with. Thus a tentative theory of ironic reversal as a source of policy failure emerges which is not only of relevance to educational policy but of wider significance

    Self-esteem is associated with premorbid adjustment and positive psychotic symptoms in early psychosis

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    <p>Abstract</p> <p>Background</p> <p>Low levels of self-esteem have been implicated as both a cause and a consequence of severe mental disorders. The main aims of the study were to examine whether premorbid adjustment has an impact on the subject's self-esteem, and whether lowered self-esteem contributes to the development of delusions and hallucinations.</p> <p>Method</p> <p>A total of 113 patients from the Thematically Organized Psychosis research study (TOP) were included at first treatment. The Positive and Negative Syndrome Scale (PANSS) was used to assess present symptoms. Premorbid adjustment was measured with the Premorbid Adjustment Scale (PAS) and self-esteem by the Rosenberg Self-Esteem Scale (RSES).</p> <p>Results</p> <p>Premorbid social adjustment was significantly related to lower self-esteem and explained a significant proportion of the variance in self-esteem. Self-esteem was significantly associated with the levels of persecutory delusions and hallucinations experienced by the patient and explained a significant proportion of the variance even after adjusting for premorbid functioning and depression.</p> <p>Conclusion</p> <p>There are reasons to suspect that premorbid functioning is an important aspect in the development of self- esteem, and, furthermore, that self-esteem is associated with the development of delusions and hallucinations.</p
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