320 resultados para Aircraft survival equipment


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Purpose: Genetic factors are important in the etiology and pathogenesis of chronic lymphocytic leukemia (CLL), Hodgkin's lymphoma (HL), and non-Hodgkin's lymphoma (NHL). Only a few small studies have assessed clinical characteristics and prognosis for familial patients, with inconsistent findings. Methods: Using population-based registries from Sweden and Denmark, 7,749 patients with CLL, 7,476 patients with HL, and 25,801 patients with NHL with linkable first-degree relatives were identified. Kaplan-Meier curves were constructed to compare survival in patients with lymphoma with and without a family history of lymphoma. The risk of dying was assessed using adjusted Cox proportional hazard models. Results: We found 85 patients with CLL (1.10%), 95 patients with HL (1.28%), and 206 patients with NHL (0.80%) with a family history of any lymphoma. Five-year mortality was similar for patients with CLL (hazard ratio [HR], 1.28; 95% CI, 0.95 to 1.72), HL (HR, 0.78; 95% CI, 0.49 to 1.25), and NHL (HR, 0.91; 95% CI, 0.74 to 1.12) versus without a family history of any lymphoma. Mortality was also similar for patients with versus without a family history of the same lymphoma. T-cell/anaplastic lymphoma patients with a family history of NHL had poorer outcome 5-years after diagnosis (HR, 5.38; 95% CI, 1.65 to 17.52). Results were similar for 10 years of follow-up. Conclusion: With the exception of T-cell/anaplastic lymphoma, survival patterns for patients with CLL, HL, and NHL with a family history of lymphoma were similar to those for sporadic patients, suggesting that most familial lymphomas do not have an altered clinical course. Our findings provide no evidence to modify therapeutic strategies for patients with CLL, HL, or NHL based solely on family history. © 2008 by American Society of Clinical Oncology.


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A methodology to estimate the cost implications of design decisions by integrating cost as a design parameter at an early design stage is presented. The model is developed on a hierarchical basis, the manufacturing cost of aircraft fuselage panels being analysed in this paper. The manufacturing cost modelling is original and relies on a genetic-causal method where the drivers of each element of cost are identified relative to the process capability. The cost model is then extended to life cycle costing by computing the Direct Operating Cost as a function of acquisition cost and fuel burn, and coupled with a semi-empirical numerical analysis using Engineering Sciences Data Unit reference data to model the structural integrity of the fuselage shell with regard to material failure and various modes of buckling. The main finding of the paper is that the traditional minimum weight condition is a dated and sub-optimal approach to airframe structural design.

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Some critical avionic systems require cooling air via vents on the side of the aircraft, thus creating leakage points for high-intensity electromagnetic radiation. This paper presents a novel application of high-intensity radiated field (HIRF) shielding using a rectangular waveguide array, while maintaining cooling airflow requirements. Signal attenuation versus frequency and depth of the array has been calculated using closed-form equations. The simulation and measurement results are in good agreement with the calculated values. (C) 2004 Wiley Periodicals, Inc.

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After their oceanic migration, juvenile European eels Anguilla anguilla enter estuaries as glass eels, develop into pigmented elvers and migrate into fresh water. Fisheries often transfer such eels abruptly between salinities, principally glass eels and elvers from estuarine to fresh water. It is usually assumed that survival rates are high, but this required systematic investigation. Survival was found to be 100% over 21 days of glass eels and semipigmented elvers transferred abruptly from estuary conditions into fresh water, 50% sea water and full sea water. Fully pigmented elvers, however, showed significantly reduced survival when transferred into sea water. Salinity preference experiments with juvenile eels have historically been inconclusive. Here, in a choice chamber design, a clear developmental shift in salinity preference was found, with glass eels preferring 100% sea water, semipigmented elvers showing no clear preference and fully pigmented elvers preferring fresh water. We conclude that eel fisheries enhancement by abrupt transfer of juveniles among salinities is largely vindicated. In addition, developmental shifts in salinity preference have been clarified and this aids in the interpretation of eel migration patterns.