2,515 research outputs found

    Ultra Bright LED Light Injection Calibration System for MINOS

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    We describe here a proposal for a light injection calibration system for the MINOS detectors based on ultra bright blue LEDs as the light source. We have shown that these LEDs are bright enough to span over two orders of magnitude in light intensity, commensurate with that expected in a single scintillator strip in the MINOS neutrino detectors.Comment: 9 pages, 13 figures, Submitted to NI

    An evaluation of head-up displays in civil transport operations

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    To determine the advantages and disadvantages of head-up displays (HUD) in civil transport approach and landing operations, an operational evaluation was conducted on the flight simulator for advanced aircraft at Ames. A non-conformal HUD concept which contained raw data and Flight Director command information, and a conformal, flight path HUD concept was designed to permit terminal area maneuvering, intercept, final approach, flare, and landing operations. Twelve B-727 line pilots (Captains) flew a series of precision and non-precision approaches under a variety of environmental and operational conditions, including wind shear, turbulence and low ceilings and visibilities. A preliminary comparison of various system and pilot performance measures as a function of display type (Flight Director HUD, Flight Path HUD, or No HUD) indicates improvements in precision and accuracy of aircraft flight path control when using the HUDs. The results also demonstrated some potentially unique advantages of a flight path HUD during non-precision approaches

    Chronic Progressive External Ophthalmoplegia Is Associated with a Novel Mutation in the Mitochondrial tRNA(Asn) Gene

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    Chronic progressive external ophthalmoplegia (CPEO) is caused by a decreased oxidative phosphorylation (OXPHOS) activity due to large-scale deletions of the mitochondrial genome in 50 % of the patients. The deletions encompass structural OXPHOS genes as well as tRNA genes, required for their expression so that the pathogenesis could be due to the deleted OXPHOS subunits or to an impaired mitochondrial translation. We have analyzed the mitochondrial genome of a patient presenting with CPEO for single base substitutions and discovered a novel heteroplasmic mutation in the tRNAAsn gene at position 5692 that converts a highly conserved adenine into a guanine. This mutation is unique because it is located at the transition of the anticodon loop to the anticodon stem and it leads to an additional base pair, thus reducing the number of loop-forming nucleotides from seven to five. Our findings suggest that CPEO can be caused by a single base substition in a mitochondrial tRNA gene so that the mitochondrial protein synthesis becomes the rate limiting step in OXPHOS fidelity

    Crew factors in flight operations. Part 3: The operational significance of exposure to short-haul air transport operations

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    Excessive flightcrew fatigue has potentially serious safety consequences. Laboratory studies have implicated fatigue as a causal factor associated with varying levels of performance deterioration depending on the amount of fatigue and the type of measure utilized in assessing performance. These studies have been of limited utility because of the difficulty of relating laboratory task performance to the demands associated with the operation of a complex aircraft. The performance of 20 volunteer twin-jet transport crews is examined in a full-mission simulator scenario that included most aspects of an actual line operation. The scenario included both routine flight operations and an unexpected mechanical abnormality which resulted in a high level of crew workload. Half of the crews flew the simulation within two to three hours after completing a three-day, high-density, short-haul duty cycle (Post-Duty condition). The other half flew the scenario after a minimum of three days off duty (Pre-Duty) condition). The results revealed that, not surprisingly, Post-Duty crews were significantly more fatigued than Pre-Duty crews. However, a somewhat counter-intuitive pattern of results emerged on the crew performancemeasures. In general, the performance of Post-Duty crews was significantly better than that of Pre-Duty crews, as rated by an expert observer on a number of dimensions relevant to flight safety. Analyses of the flightcrew communication patterns revealed that Post-Duty crews communicated significantly more overall, suggesting, as has previous research, that communication is a good predictor of overall crew performance

    Nonlinear interplay of Alfven instabilities and energetic particles in tokamaks

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    The confinement of energetic particles (EP) is crucial for an efficient heating of tokamak plasmas. Plasma instabilities such as Alfven Eigenmodes (AE) can redistribute the EP population making the plasma heating less effective, and leading to additional loads on the walls. The nonlinear dynamics of toroidicity induced AE (TAE) is investigated by means of the global gyrokinetic particle-in-cell code ORB5, within the NEMORB project. The nonperturbative nonlinear interplay of TAEs and EP due to the wave-particle nonlinearity is studied. In particular, we focus on the nonlinear modification of the frequency, growth rate and radial structure of the TAE, depending on the evolution of the EP distribution in phase space. For the ITPA benchmark case, we find that the frequency increases when the growth rate decreases, and the mode shrinks radially. This nonlinear evolution is found to be correctly reproduced by means of a quasilinear model, namely a model where the linear effects of the nonlinearly modified EP distribution function are retained.Comment: Submitted to Plasma Phys. Control. Fusio

    Commercial use of evidence in public health policy:A critical assessment of food industry submissions to global-level consultations on non-communicable disease prevention

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    Background Ultra-processed food industry (UPFI) actors have consistently opposed statutory regulation in health policy debates, including at the WHO. They do so most commonly with claims that regulatory policies do not work, will have negative consequences or that alternatives such as self-regulation work well or better. Underlying this are often assertions that industry is aligned with principles of evidence-based policymaking. In this study, we interrogate if this holds true by exploring the extent and quality of the evidence UPFI respondents employed to support claims around regulatory policy, and how they did this.Methods First, we identified all submissions from organisations who overtly represent UPFI companies to consultations held by the WHO on non-communicable disease policy between 2016 and 2018. Second, we extracted all relevant factual claims made in these submissions and noted if any evidence was referenced in support. Third, we assessed the quality of evidence using independence from UPFI, nature, and publication route as indicators. Lastly, where peer-reviewed research was cited, we examined if the claims made could be justified by the source cited.Results Across 26 included consultation responses, factual claims around regulation were made in 18, although only 10 referenced any evidence at all. Of all 114 claims made, 39 pieces of identifiable evidence were cited in support of 56 claims. Of the 39 distinct pieces of evidence, two-thirds were industry-funded or industry-linked, with only 16 externally peer-reviewed. Over half of industry-funded or industry-linked academic articles failed to declare a conflict of interest (COI). Overall, of only six claims which drew on peer-reviewed and independent research, none appropriately represented the source.Discussion UPFI respondents made far-reaching claims which were rarely supported by high-quality, independent evidence. This indicates that there may be few, if any, benefits from consulting actors with such a clear COI

    Big food and the World Health Organization:A qualitative study of industry attempts to influence global-level non-communicable disease policy

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    Introduction There is an urgent need for effective action to address the over 10 million annual deaths attributable to unhealthy diets. Food industry interference with policies aimed at reducing non-communicable diseases (NCDs) is widely documented at the national level but remains under-researched at the global level. Thus, this study explores how ultra-processed food industry actors have attempted to influence NCD policy at WHO.Methods A combination of inductive and deductive thematic coding of internal industry documents, academic literature and interviews with key informants from international organisations and global civil society was used to identify action-based strategies ultra-processed food industry actors employ to influence global-level policy.Results Ultra-processed food industry actors have attempted to influence WHO and its policies through three main action-based strategies: coalition management, involvement in policy formulation, and information management. Coalition management includes the creation and use of overt alliances between corporations—business associations—and more covert science-focused and policy-focused intermediaries, the hiring of former WHO staff and attempted co-option of civil society organisations. Industry involvement in policy formulation is operationalised largely through the lobbying of Member States to support industry positions, and business associations gaining access to WHO through formal consultations and hearings. Information management involves funding and disseminating research favourable to commercial interests, and challenging unfavourable evidence.Conclusion We provide novel insights into how ultra-processed food industry actors shape global-level NCD policy and identify a clear need to guard against commercial interference to advance NCD policy. In their approach, the political behaviour of multinational food corporations bears similarities to that of the tobacco industry. Increased awareness of, and safeguarding against, commercial interference at the national as well as the global level have the potential to strengthen the crucial work of WHO

    An Operational evaluation of head up displays for civil transport operations. NASA/FAA phase 3 report

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    The advantages and disadvantages of head-up displays (HUDs) in commercial jet transport approach and landing operations was evaluated. Ten airline captains currently qualified in the B-727 aircraft flew a series of instrument landing system (ILS) and nonprecision approaches in a motion base simulator using both a flight director HUD concept and a flightpath HUD concept as well as conventional head-down instruments under a variety of environmental and operational conditions to assess: (1) the potential benefits of these HUDs in airline operations; (2) problems which might be associated with their use; and (3) flight crew training requirements and flight crew operating procedures suitable for use with the HUDs. Results are presented in terms of objective simulator based performance measures, subject pilot opinion and rating data, and observer data

    A Method for the Study of Human Factors in Aircraft Operations

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    A method for the study of human factors in the aviation environment is described. A conceptual framework is provided within which pilot and other human errors in aircraft operations may be studied with the intent of finding out how, and why, they occurred. An information processing model of human behavior serves as the basis for the acquisition and interpretation of information relating to occurrences which involve human error. A systematic method of collecting such data is presented and discussed. The classification of the data is outlined

    Corporate political activity in the context of sugar-sweetened beverage tax policy in the WHO European Region

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    BACKGROUND: Sugar-sweetened beverage (SSB) taxes have emerged as an effective and increasingly popular tool to reduce added sugar intake, an important contributor to obesity and non-communicable diseases. A common barrier to the implementation of well-designed SSB taxes is the opposition of commercial actors. Focusing on the WHO European Region, this study seeks to map if and how key stakeholders have experienced industry efforts to influence SSB taxes. METHODS: We identified 11 countries in the WHO European Region which have implemented SSB taxes or attempted to do so. Using an online survey informed by the global literature on industry interference with SSB taxation, we approached 70 in-country policymakers, advocates and academics. The data were analysed using an existing framework of corporate political activity. RESULTS: Twenty-three experts from nine countries responded to the survey. Transnational SSB producers and their business associations were identified as the most active opponents of SSB taxation. Industry claims that the policy would have negative economic effects were identified as the most common and powerful arguments. Direct lobbying was reported in all study countries. Shifts in political activity were recognisable across stages of the policy process, moving from outright opposition to attempts to delay or weaken the policy after its announcement. CONCLUSION: Those seeking to introduce effective SSB taxation can use our findings to pre-empt and counter industry opposition. We identify several measures for preventing and mitigating industry interference with SSB tax policy
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