37 research outputs found

    Advanced Configurations for Very Large Subsonic Transport Airplanes

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    Recent aerospace industry interest in developing a subsonic commercial transport airplane with 50 percent greater passenger capacity than the largest existing aircraft in this category (the Boeing 747-400 with approximately 400-450 seats) has generated a range of proposals based largely on the configuration paradigm established nearly 50 years ago with the Boeing B-47 bomber. While this basic configuration paradigm has come to dominate subsonic commercial airplane development since the advent of the Boeing 707/Douglas DC-8 in the mid-1950's, its extrapolation to the size required to carry more than 600-700 passengers raises several questions. To explore these and a number of related issues, a team of Boeing, university, and NASA engineers was formed under the auspices of the NASA Advanced Concepts Program. The results of a Research Analysis focused on a large, unconventional transport airplane configuration for which Boeing has applied for a patent are the subject of this report. It should be noted here that this study has been conducted independently of the Boeing New Large Airplane (NLA) program, and with the exception of some generic analysis tools which may be common to this effort and the NLA (as will be described later), no explicit Boeing NLA data other than that published in the open literature has been used in the conduct of the study reported here

    Melanoma Patients with Positive Sentinel Nodes Who Did Not Undergo Completion Lymphadenectomy: A Multi-Institutional Study

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    Completion lymph node dissection (CLND) is considered the standard of care in melanoma patients found to have sentinel lymph node (SLN) metastasis. However, the therapeutic utility of CLND is not known. The natural history of patients with positive SLNs who do not undergo CLND is undefined. This multi-institutional study was undertaken to characterize patterns of failure and survival rates in these patients and to compare results with those of positive-SLN patients who underwent CLND.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45875/1/10434_2006_Article_10237.pd

    Bortezomib-based immunosuppression after reduced-intensity conditioning hematopoietic stem cell transplantation: randomized phase II results

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    Aprior phase I/II trial of bortezomib/tacrolimus/methotrexate prophylaxis after human leukocyte antigen (HLA)-mismatched reduced intensity conditioning allogeneic hematopoietic stem cell transplantation documented low acute graft-versus-host disease incidence, with promising overall and progression-free survival. We performed an open-label three-arm 1:1:1 phase II randomized controlled trial comparing grade II–IV acute graft-versus-host disease between conventional tacrolimus/methotrexate (A) versus bortezomib/tacrolimus/methotrexate (B), and versus bortezomib/sirolimus/tacrolimus (C), in reduced intensity conditioning allogeneic transplantation recipients lacking HLA-matched related donors. The primary endpoint was grade II–IV acute graft-versus-host disease incidence rate by day +180. One hundred and thirty-eight patients (A 46, B 45, C 47) with a median age of 64 years (range: 24–75), varying malignant diagnoses and disease risk (low 14, intermediate 96, high/very high 28) received 7–8/8 HLA-mismatched (40) or matched unrelated donor (98) grafts. Median follow up in survivors was 30 months (range: 14–46). Despite early immune reconstitution differences, day +180 grade II-IV acute graft-versus-host disease rates were similar (A 32.6%, B 31.1%, C 21%; P=0.53 for A vs. B, P=0.16 for A vs. C). The 2-year non-relapse mortality incidence was similar (A 14%, B 16%, C 6.4%; P=0.62), as were relapse (A 32%, B 32%, C 38%; P=0.74), chronic graft-versus-host disease (A 59%, B 60% C 55%; P=0.66), progression-free survival (A 54%, B 52%, C 55%; P=0.95), and overall survival (A 61%, B 62%, C 62%; P=0.98). Overall, the bortezomib-based regimens evaluated did not improve outcomes compared with tacrolimus/methotrexate therapy. clinicaltrials.gov Identifier: 0175438

    Some Systemic Issues in the Development of the Aerospace Industry Technical Workforce of the Future

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    This paper is a continuation of the authors’ previous examinations of a suite of issues surrounding the putative decline in aeronautics in this country. The purpose of this paper is to discuss three specific issues believed to be of particular importance to the future of our industry. The first is the question of how many engineers we may need in our future as we confront the problem of an aging workforce and the globalization of our industry. The second is the question of what skills and abilities these engineers will need to possess as the overall industry continues to evolve. Finally, the need for more systems-oriented, multidisciplinary-skilled talent is addressed. A basic message of the paper carried on from earlier writings is that while aeronautics may indeed be a “maturing industry” (at least in some major traditional product areas), there is much that we can and should do to create a vision of our future as vivid as that which has driven our past as a means to attract and develop the talent needed to assure the future of our enterprise. Without this talent, few of the major technological advances that can be currently foreseen can come to fruition

    Technology and You: Working with the Aerospace Industry to Enhance Engineering Education

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    While many engineers in the aerospace engineering profession know that interacting with students is a good idea, few of them know how to do it. Certainly some engineers are asked on occasion to give lectures at various university club meetings, and some are even heavily involved in interacting with students working on various design projects, but the average engineer has little or no interaction with students over the course of their career. A number of companies, including Boeing, have created technical interest groups to encourage mentoring and sharing of corporate knowledge throughout the company. These efforts have been met with varying degrees of success. In an effort to improve this situation, the Boeing Technology Interest Group concept has been modified and expanded to include students within the groups. Concepts for including students (both graduate and undergraduate) and faculty are discussed, including details about how the concept could be integrated into existing research and educational programs. Conclusions are drawn about the feasibility of the concept and suggestions for implementation are made

    The Demise of Aerospace, Part 2. We Doubt It.

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