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The aim of this study was to explore the role of protein kinase C (PKC) in the activation of mitogen-activated protein kinases (MAPK) in T lymphocytes. The MAPK extracellular signal-regulated kinase-2 (ERK2) is activated in response to phorbol esters which stimulate PKC, by transient expression of a constitutively active ras mutant, by cell activation via the G protein-coupled type 1 muscarinic acetylcholine receptor (HM1R) or in response to triggering of the T cell antigen receptor (TCR). The relative contribution of PKC to TCR and HM1R regulation of ERK2 was explored by examining the effects of a PKC inhibitor (Ro 31-8425) on ERK2 activation. The data demonstrate that phorbol ester and HM1R regulation of ERK2 was prevented by the PKC inhibitor, but that the inhibitor had no effect on ERK2 activation induced by expression of a constitutively active ras mutant p21v-Ha-ras. Furthermore, the TCR stimulates both PKC and p21(ras) but TCR regulation of ERK2 was only weakly suppressed by the PKC inhibitor. These data indicate that PKC has a potential but not a predominant role in TCR regulation of ERK2.

A simulation study was undertaken to determine the effect of traffic-sensor noise on the ability of a pilot to perform an in-trail spacing task. The tests were conducted in a fixed-base cockpit simulator configured as a current-generation transport aircraft, with an electronic traffic display provided in the weather-radarscope location. The true positions of the traffic were perturbed in both relative range and azimuth by random errors to simulate traffic-sensor noise associated with an onboard sensor. The evaluation task involved simulated instrument approaches into a terminal area while maintaining self-separation on a lead aircraft. Separation performance data and pilot subjective ratings and comments were obtained during the study.

The principal operational improvements desired by commercial aircraft operators in the United States are efficient aircraft operations and delay reductions at the major terminals. This paper describes efforts underway within the Advanced Transport Operating Systems Program at the Langley Research Center to provide a technology basis for reducing delay while improving aircraft efficiency. The principal thrust is the development of time-based traffic control concepts which could be used within the framework of the upgraded National Airspace System and which would allow conventionally equipped aircraft to operate in a manner compatible with advanced aircraft., This article is from 'Efficient Conduct of Individual Flights and Air Traffic or Optimum Utilization of Modern Technology for the Overall Benefit of Civil and Military Airspace Users. Conference Proceedings of the Symposium of the Guidance and Control Panel (42nd) Held in Brussels, Belgium on 10-13 June 1986,' AD-A182 150, p43-1-43-14.

A joint NASA-FAA program is being conducted to explore the potential benefits and liabilities of Cockpit Display of Traffic Information (CDTI) for a broad range of applications. As part of this effort, piloted simulations have been conducted to determine the effect of various display parameters and separation criteria on terminal area in-trail following using CDTI. Both a conventional air carrier configuration, wherein the traffic data is presented on a centrally located weather radar scope, and an advanced configuration, where the data is superimposed on the primary navigation display, have been investigated. The scenarios employed have ranged from following a single lead aircraft to following multiple CDTI-equipped aircraft queues. This paper summarizes the results of these experiments and discusses their implications on the design and use of CDTI for in-trail separation., This article is from 'Proceedings of the Annual Conference on Manual Control (18th) Held at Dayton, Ohio on 8-10 June 1982,' AD-A131 256. p485-513.