3,274 research outputs found
On the USAF ‘risk of failure’ approach and its applicability to composite repairs to metal airframes
The USAF report on the risk analysis of aging aircraft fleets notes that the operational life of individual airframes is seldom equal to the design life of the fleet and that the life of an aircraft fleet t ends to be determined more by its inherent operational capability and maintenance costs rather than by the number of flight hours specified at the design stage. As such this paper focuses on whether the USAF approach to risk assessment can be used for airf rames repaired with a composite patch/doubler. To this end the present paper describes a test program designed to study the effect of adhesively -bonded composite repairs to fatigue cracks that, prior to repair, have grown from small naturally -occurring mat erials discontinuities. This study reveals that crack growth in composite repairs conforms to the exponential growth equation used in the USAF approach to assessing the risk of failure. Furthermore, the exponent, ω, in the exponential growth law can be de termined from the crack growth history associated with the unrepaired specimens and the simple reduction in the stress due to the application of the composite patch/doubler, using the ‘cubic rule’ that was previously used to assess crack growth in the RAAF F/A -18 (Hornet) fleet
Achievement of combined goals of low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol with three different statins: Results from VOYAGER
AbstractBackgroundGuidelines suggest that the combination of low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) is the most clinically relevant goal for lipid-lowering treatments.MethodsData from VOYAGER, an individual patient data meta-analysis including 32,258 patients from 37 clinical trials, was used to determine the percentage of patients reaching combined goals of LDL-C and non-HDL-C following treatment with simvastatin, atorvastatin, or rosuvastatin. Paired comparisons were made between each dose of rosuvastatin and the same or higher doses of simvastatin and atorvastatin.ResultsEach dose of rosuvastatin brought significantly more patients to the combined goal of LDL-C < 100 mg/dL and non-HDL-C < 130 mg/dL than the same or double dose of atorvastatin; atorvastatin 80 mg was significantly superior to rosuvastatin 10 mg (all p < 0.001). Each dose of rosuvastatin helped significantly more patients reach the combined goal than any dose of simvastatin (all p < 0.001), except for rosuvastatin 10 mg versus simvastatin 80 mg (non-significant). Also, each dose of rosuvastatin helped significantly more patients to reach the combined goal of LDL-C < 70 mg/dL and non-HDL-C < 100 mg/dL than the same or double dose of atorvastatin (all p < 0.001). Every dose of rosuvastatin was significantly superior to all doses of simvastatin (all p ≤ 0.020), except for rosuvastatin 10 mg versus simvastatin 40 mg and 80 mg (non-significant).ConclusionsPhysicians' choice of statin and dose is important in helping patients achieve the combined LDL-C and non-HDL-C goals recommended in established guidelines
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Ion cyclotron resonant heating 2 x 170/sup 0/ loop antenna for the Tandem Mirror Experiment-Upgrade
This paper reviews the mechanical design and improvements that have taken place on the loop type ion cyclotron resonance heating (ICRH) antennas that are located in the center cell region of the Tandem Mirror Experiment-Upgrade (TMX-U)
Validation of a Multivariate Serum Profile for Epithelial Ovarian Cancer Using a Prospective Multi-Site Collection
In previous studies we described the use of a retrospective collection of ovarian cancer and benign disease samples, in combination with a large set of multiplexed immunoassays and a multivariate pattern recognition algorithm, to develop an 11-biomarker classification profile that is predictive for the presence of epithelial ovarian cancer. In this study, customized, Luminex-based multiplexed immunoassay kits were GMP-manufactured and the classification profile was refined from 11 to 8 biomarkers (CA-125, epidermal growth factor receptor, CA 19-9, C-reactive protein, tenascin C, apolipoprotein AI, apolipoprotein CIII, and myoglobin). The customized kits and the 8-biomarker profile were then validated in a double-blinded manner using prospective samples collected from women scheduled for surgery, with a gynecologic oncologist, for suspicion of having ovarian cancer. The performance observed in model development held in validation, demonstrating 81.1% sensitivity (95% CI 72.6 – 87.9%) for invasive epithelial ovarian cancer and 85.4% specificity (95% CI 81.1 – 88.9%) for benign ovarian conditions. The specificity for normal healthy women was 95.6% (95% CI 83.6 – 99.2%). These results have encouraged us to undertake a second validation study arm, currently in progress, to examine the performance of the 8-biomarker profile on the population of women not under the surgical care of a gynecologic oncologist
Compatibility and combination of world W -boson mass measurements
The compatibility of W-boson mass measurements performed by the ATLAS, LHCb, CDF, and D0 experiments is studied using a coherent framework with theory uncertainty correlations. The measurements are combined using a number of recent sets of parton distribution functions (PDF), and are further combined with the average value of measurements from the Large Electron–Positron collider. The considered PDF sets generally have a low compatibility with a suite of global rapidity-sensitive Drell–Yan measurements. The most compatible set is CT18 due to its larger uncertainties. A combination of all mW measurements yields a value of mW=80, 394.6±11.5 MeV with the CT18 set, but has a probability of compatibility of 0.5% and is therefore disfavoured. Combinations are performed removing each measurement individually, and a 91% probability of compatibility is obtained when the CDF measurement is removed. The corresponding value of the W boson mass is 80, 369.2±13.3 MeV, which differs by 3.6σ from the CDF value determined using the same PDF set
Factors influencing awareness of community-based shorebird conservation projects in Australia
We examine the awareness of potential volunteers (n = 360) living near nine community-based shorebird conservation projects. About half of the people sampled (54%) were unaware of the nearest project. Awareness of interviewees varied substantially among projects (28-78%). Apart from gaining awareness of projects through membership of natural history groups (43%), many respondents heard of projects through friends and relatives (20%), rather than through media such as newspapers (14%) and television (2.3%). We demonstrate that community-based projects can be quantitatively and critically assessed for awareness. The use of rapid, cost-effective assessments of awareness levels has application in many conservation projects. <br /
The microRNA-29 family in cartilage homeostasis and osteoarthritis
MicroRNAs have been shown to function in cartilage development and homeostasis, as well as in progression of osteoarthritis. The objective of the current study was to identify microRNAs involved in the onset or early progression of osteoarthritis and characterise their function in chondrocytes. MicroRNA expression in mouse knee joints post-DMM surgery was measured over 7 days. Expression of miR-29b-3p was increased at day 1 and regulated in the opposite direction to its potential targets. In a mouse model of cartilage injury and in end-stage human OA cartilage, the miR-29 family were also regulated. SOX9 repressed expression of miR-29a-3p and miR-29b-3p via the 29a/b1 promoter. TGFβ1 decreased expression of miR-29a, b and c (3p) in primary chondrocytes, whilst IL-1β increased (but LPS decreased) their expression. The miR-29 family negatively regulated Smad, NFκB and canonical WNT signalling pathways. Expression profiles revealed regulation of new WNT-related genes. Amongst these, FZD3, FZD5, DVL3, FRAT2, CK2A2 were validated as direct targets of the miR-29 family. These data identify the miR-29 family as microRNAs acting across development and progression of OA. They are regulated by factors which are important in OA and impact on relevant signalling pathways
Ethical issues, research and vulnerability : gaining the views of children and young people in residential care
Children and young people in residential care are some of the most vulnerable in our society. They may have experienced violence and physical, sexual or emotional abuse. They may be involved in offending or the misuse of drugs and alcohol. They are separated from their families and have to cope with living in a group situation with other young people and staff members. Children and young people in residential care also possess strengths, competencies and resilience. We have much to learn from their experiences and perspectives, both generally and surrounding their time in care. This paper will address the ethical issues which arise from gaining the views of children and young people in residential care, drawing on the experience of carrying out three studies in particular (Kendrick et al. 2004, The development of a residential unit working with sexually aggressive young men. In: H.G. Eriksson and T. Tjelflaat, eds. Residential care: horizons for the new century. Aldershot: Ashgate, 38-55; Docherty et al. 2006, Designing with care: interior design and residential child care. Farm7 and SIRCC. http://www.sircc.strath.ac.uk/publications/Designing_with_Care.pdf; Steckley, L. and Kendrick, A., 2005. Physical restraint in residential child care: the experiences of young people and residential workers. Childhoods 2005: Children and Youth in Emerging and Transforming Societies, University of Oslo, Norway, 29 June-3 July 2005, Steckley and Kendrick 2007, Young people's experiences of physical restraint in residential care: subtlety and complexity in policy and practice. In: M. Nunno, L. Bullard and D. Day, eds. For our own safety: examining the safety of high-risk interventions for children and young people. Washington, DC: Child Welfare League of America, forthcoming). The paper will discuss: information, consent and choice about involvement in the research; confidentiality, privacy and safety. It will also explore some of the more complex issues of ethical good practice which arise from researching children in their own living space. The negotiation of children's time and space must be approached carefully, with consideration of their rights and wishes. Sensitivity to children and young people's priorities and preoccupations must be paramount
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Search for lepton-flavour-violating decays of Higgs-like bosons.
A search is presented for a Higgs-like boson with mass in the range 45 to 195 GeV/c2 decaying into a muon and a tau lepton. The dataset consists of proton-proton interactions at a centre-of-mass energy of 8 TeV , collected by the LHCb experiment, corresponding to an integrated luminosity of 2 fb-1 . The tau leptons are reconstructed in both leptonic and hadronic decay channels. An upper limit on the production cross-section multiplied by the branching fraction at 95% confidence level is set and ranges from 22 pb for a boson mass of 45 GeV/c2 to 4 pb for a mass of 195 GeV/c2
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