1,588 research outputs found

    The impact of changing technology on the demand for air transportation

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    Demand models for air transportation that are sensitive to the impact of changing technology were developed. The models are responsive to potential changes in technology, and to changing economic, social, and political factors as well. In addition to anticipating the wide differences in the factors influencing the demand for long haul and short haul air travel, the models were designed to clearly distinguish among the unique features of these markets

    The state-of-the-art in air transportation demand and systems analysis : a report on the proceedings of a workshop sponsored by the Civil Aeronautics Board, Department of Transportation, and National Aeronautics and Space Administration (June 1975)

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    August 1975Introduction and summary: Forecasting air transportation demand has indeed become a complex and risky business in recent years, especially in view of unpredictable fuel prices, high inflation rates, a declining rate of aggregate population growth, and an uncertainty with respect to the regulatory structure in the aviation industry. Since the stakes are very high, the need for accurate forecasting and for a more complete understanding of the total system of air transportation continues to grow. Past forecasting methods have become inadequate for at least two reasons. First, the trend extrapolation method of forecasting is no longer appropriate due to the significant changes in both the economic and the operating environments in recent years. Second, the more sophisticated econometric forecasting models are only as good as our understanding of the total air transportation system on the one hand, and the availability of data on the other. In light of these deficiencies, the dual needs for improving forecasting methods and for increasing the reliability of data are more critical now than ever before. In short, there is a compelling need to perform basic research to improve both the forecasting methods and the data in the aviation industry. Among the various types of forecasts of aviation activity desired by the government agencies, the air carriers, the airframe and engine manufacturers, the airport authorities, and the financial community, one component that plays a critical role in long-range planning pertains to the future fleet requirements for the aviation industry. Forecast items needed with respect to future fleet requirements include types, configuration, ranges, and technologies of new aircraft so that the industry and government can coordinate their resources to maximize the interests of the producers, regulators and consumers of future air service. The National Aeronautics and Space Administration (NASA), with its twin missions of both aeronautics and astronautics, has been focusing its attention on the aeronautics component in recent years. In this overall responsibility, the Systems Study Division of NASA-Ames Research Center has as one of its main objectives the development of a better understanding of the civil air transportation system in the United States, with emphasis placed on the proper and timely application of new technology. In order to fulfill this objective, the division has a critical need for projections of the growth of demand and for the determination of the role of technology in the future growth of air transportation. Before undertaking an extensive research effort in the area of air transportation demand analysis and forecasting, NASA-Ames attempted to solicit the views of the industry and other government agencies at a one day informal meeting in San Francisco in December 1974. The meeting was attended by about twenty experts from the carriers, airframe and engine manufacturers, U.S. Department of Transportation, universities and NASA. The goals of this mini-workshop were three-fold: the first objective was to determine the ways in which the NASA-Ames Systems Study Division could play a supportive role in this area; second, it was essential to receive an informal endorsement from the industry and other government agencies; and third, it was necessary to determine the direction for the proposed research. This meeting concluded with a general agreement on a definite need for future research, with the belief that not only could NASA-Ames play a supportive role but, more important, that it could play a catalytic role. However, due to the limited participation in this one-day meeting and the assistance that the proposed research could have provided to a wide variety of users, a more extensive workshop was proposed at that time, possibly to be co-sponsored by other government agencies. Subsequent to the December 1974 meeting, further discussions with the U.S. Civil Aeronautics Board (CAB) and the U.S. Department of Transportation (DOT) resulted in a three-day workshop co-sponsored by the CAB, DOT and NASA. The reasons for the joint sponsorship by the CAB and DOT reflected a desire from these agencies to participate in the search for methodologies and information on the long-range benefits, problems and issues of technological advances in aviation and to assist NASA in deploying its funds on these matters in the most productive and efficient ways. The overall objectives of this workshop were four-fold: first, to investigate the state-of-the-art in air transportation demand forecasting; second, to determine the needs of the various government agencies and the industry; third, to assess the possibility of long-term government sponsorship of basic research to improve the forecasting of air transportation activity; and fourth, to determine the most promising areas of research in air transportation and systems analysis. This workshop was organized by the Flight Transportation Laboratory of the Massachusetts Institute of Technology and the Transportation Center at Northwestern University and was held at the Mayflower Hotel in Washington, D.C. on June 2-4, 1975. The meeting was attended by one hundred experts, thirty-three of whom made extensive presentations. This report then is a summary of the highlights of the presentations delivered at the workshop, with appropriate interjections and editorial comments as perceived by its authors

    Against the Odds: Psychomotor Development of Children Under 2 years in a Sudanese Orphanage.

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    Providing abandoned children the necessary medical and psychological care as possible after their institutionalization may minimize developmental delays. We describe psychomotor development in infants admitted to an orphanage in Khartoum, Sudan, assessed at admission and over an 18-month follow-up. Psychological state and psychomotor quotients were determined using a simplified Neonatal Behavior Assessment Scale (NBAS), the Brunet-Lezine and Alarm distress baby (ADBB) scale. From May-September 2005, 151 children were evaluated 2, 4, 9, 12 and 18 months after inclusion. At admission, ∼15% of children ≤1 month had a regulation impairment according to the NBAS, and 33.8% presented a distress state (ADBB score >5). More than 85% (129/151) recovered normal psychomotor development. The results of the program reinforce the importance of early detection of psychological disorders followed by rapid implementation of psychological case management to improve the development of young children in similar institutions and circumstances

    Sharp-1 regulates TGF-β signaling and skeletal muscle regeneration

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    10.1242/jcs.136648Journal of Cell Science1273599-608JNCS

    Submucosal diclofenac for acute postoperative pain in third molar surgery: A randomized, controlled clinical trial

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    Diclofenac sodium is a widely used nonsteroidal anti-inflammatory drug (NSAID) for relief of inflammatory pain. A recent formulation combines this drug with hydroxypropyl-β-cyclodextrin (HPβCD) to improve its solubility and to enable subcutaneous administration. Previous studies confirmed the efficacy of this combination. This study’s aim was to evaluate the efficacy, safety, and local tolerability of diclofenac HPβCD administered as a local submucosal injection prior to lower third molar surgery. We conducted a prospective, randomized, double-blind, placebo-controlled, parallel-group phase II single-center study. Seventy-five patients requiring mandibular third molar surgery were randomized into 1 of 5 groups: 5 mg/1 mL diclofenac HPβCD, 12.5 mg/1 mL diclofenac HPβCD, 25 mg/1 mL diclofenac HPβCD, 50 mg/1 mL diclofenac HPβCD, or 1 mL placebo. The respective study drug was injected into the mucosal tissue surrounding the surgical site prior to surgery following achievement of local anesthesia. The primary outcome measure was the area under the curve (AUC) of cumulative pain scores from end of surgery to 6 h postsurgery. This demonstrated a global treatment effect between the active groups and placebo, hence confirming the study drug’s efficacy (P = 0.0126). Secondary outcome measures included the time until onset of pain and the time until patients required rescue medication, both showing statistical significance of the study drug compared to placebo (P < 0.0161 and P < 0.0001, respectively). The time until rescue medication ranged between 7.8 h (for 25 mg/1 mL diclofenac HPβCD) and 16 h (for 50 mg/1 mL diclofenac HPβCD). Interestingly, the 5-mg/1-mL solution appeared superior to the 12.5-mg/1-mL and 25-mg/1-mL solutions (time until rescue medication = 12.44 h). A total of 14% of patients experienced minor adverse drug reactions (ADRs), of which 2 cases demonstrated flap necrosis. These resolved without further intervention. The study results overall indicate efficacy, safety, and relative tolerability of diclofenac HPβCD used locally as a submucosal injection prior to third molar surgery (ClinicalTrials.gov NCT01706588)

    Beyond bone biology: Lessons from team science

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    Today, research in biomedicine often requires the knowledge and technologies in diverse fields. Therefore, there is an increasing need for collaborative team science that crosses traditional disciplines. Here, we discuss our own lessons from both interdisciplinary and transdisciplinary teams, which ultimately ushered us to expand our research realm beyond bone biology. This article is protected by copyright. All rights reserved

    Tunable variation of optical properties of polymer capped gold nanoparticles

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    Optical properties of polymer capped gold nanoparticles of various sizes (diameter 3-6 nm) have been studied. We present a new scheme to extract size dependent variation of total dielectric function of gold nanoparticles from measured UV-Vis absorption data. The new scheme can also be used, in principle, for other related systems as well. We show how quantum effect, surface atomic co - ordination and polymer - nanoparticle interface morphology leads to a systematic variation in inter band part of the dielectric function of gold nanoparticles, obtained from the analysis using our new scheme. Careful analysis enables identification of the possible changes to the electronic band structure in such nanoparticles.Comment: 13 pages,7 figures, 1 tabl

    ϕ\phi meson production in dd++Au collisions at sNN=200\sqrt{s_{_{NN}}}=200 GeV

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    The PHENIX experiment has measured ϕ\phi meson production in dd++Au collisions at sNN=200\sqrt{s_{_{NN}}}=200 GeV using the dimuon and dielectron decay channels. The ϕ\phi meson is measured in the forward (backward) dd-going (Au-going) direction, 1.2<y<2.21.2<y<2.2 (2.2<y<1.2-2.2<y<-1.2) in the transverse-momentum (pTp_T) range from 1--7 GeV/cc, and at midrapidity y<0.35|y|<0.35 in the pTp_T range below 7 GeV/cc. The ϕ\phi meson invariant yields and nuclear-modification factors as a function of pTp_T, rapidity, and centrality are reported. An enhancement of ϕ\phi meson production is observed in the Au-going direction, while suppression is seen in the dd-going direction, and no modification is observed at midrapidity relative to the yield in pp++pp collisions scaled by the number of binary collisions. Similar behavior was previously observed for inclusive charged hadrons and open heavy flavor indicating similar cold-nuclear-matter effects.Comment: 484 authors, 16 pages, 12 figures, 6 tables. v1 is the version accepted for publication in Phys. Rev. C. Data tables for the points plotted in the figures are given in the paper itsel
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