The Metamorphosis of the Defense Industry

The downsizing of the United States defense industry in recent years had a multitude of effects on defense and defense-related manufacturers. Besides the inevitable loss of jobs, these firms essentially had to reinvent themselves in order to compete in the commercial sector more effectively. Moreover, the defense cutbacks also resulted in implications for the U.S. as a whole. These include questionable preparedness for armed conflict, as well as the potential loss of defense-related suppliers that could affect the ability to sustain armed conflict. These and other insights were gleaned from plant-level interviews and tours of several, small defense-related manufacturers

The Ascent to Manufacturing Competitiveness: Defense Firms vs. Non-Defense Firm

Facing rapidly changing markets and increasing competition, the competitive environment of the defense industry has undergone extensive restructuring, significantly more so than for the non-defense sector. This comprehensive survey of defense and non-defense firms offers insight into the defense industry\u27s journey into open competition, as well as insight into different strategic approaches to manufacturing competitiveness during this critical period. The data suggest that the surviving defense firms have strengthened, and that defense and non-defense manufacturers alike are responding competitively to the call of the global economy

Development of space-stable thermal-control coatings Triannual report, 1 Nov. 1967 - 29 Feb. 1968

Reactive encapsulation methods for thermal stabilization of zinc orthotitanate resin paints for spacecrafts material

The electronic spectra of protonated PANH molecules

Aims. This study was designed to examine the viability of protonated nitrogen-substituted polycyclic aromatic hydrocarbons (H+PANHs) as candidates for the carriers of the diffuse interstellar bands (DIBs). Methods. We obtained the electronic spectra of two protonated PANH cations, protonated acridine and phenanthridine, using parent ion photo-fragment spectroscopy and generated theoretical electronic spectra using ab initio calculations. Results. We show that the spectra of the two species studied here do not correspond to known DIBs. However, based on the general properties derived from the spectra of these small protonated nitrogen-substituted PAHs, we propose that larger H+PANH cations represent good candidates for DIB carriers due to the expected positions of their electronic transitions in the UV-visible and their narrow spectral bands.Comment: 7 pages, 2 figures, accepted for publication in A&

IL-12 and IL-4 activate a CD39-dependent intrinsic peripheral tolerance mechanism in CD8+ T cells

Immune responses to protein antigens involve CD4+ and CD8+ T cells, which follow distinct programs of differentiation. Naïve CD8 T cells rapidly develop cytotoxic T-cell (CTL) activity after T-cell receptor stimulation, and we have previously shown that this is accompanied by suppressive activity in the presence of specific cytokines, i.e. IL-12 and IL-4. Cytokine-induced CD8+ regulatory T (Treg) cells are one of several Treg-cell phenotypes and are Foxp3− IL-10+ with contact-dependent suppressive capacity. Here, we show they also express high level CD39, an ecto-nucleotidase that degrades extracellular ATP, and this contributes to their suppressive activity. CD39 expression was found to be upregulated on CD8+ T cells during peripheral tolerance induction in vivo, accompanied by release of IL-12 and IL-10. CD39 was also upregulated during respiratory tolerance induction to inhaled allergen and on tumor-infiltrating CD8+ T cells. Production of IL-10 and expression of CD39 by CD8+ T cells was independently regulated, being respectively blocked by extracellular ATP and enhanced by an A2A adenosine receptor agonist. Our results suggest that any CTL can develop suppressive activity when exposed to specific cytokines in the absence of alarmins. Thus negative feedback controls CTL expansion under regulation from both nucleotide and cytokine environment within tissues

On-line computer control of turbine generators using state estimation and optimal feedback

Imperial Users onl

Analytic studies in the learning and memory of skilled performance second semi-annual report, oct. 1, 1964 - mar. 30, 1965

Analytic studies in learning and memory of skilled performanc

Artificial life: Discipline or method? Report on a debate held at ECAL99

How can artificial life (AL) advance scientific understanding? Is AL best seen as a new discipline, or as a collection of novel computational methods that can be applied to old problems? And given that the products of AL research range from abstract existence proofs to working robots to detailed simulation models, are there standards of quality or usefulness that can be applied across the whole field? On September 16th, 1999 in Lausanne, Switzerland, a debate on these questions was held as part of the Fifth European Conference on Artificial Life. As the organizers, we wanted to foster a constructive discussion regarding the scientific status, and future, of AL. We were well aware that some of these issues had been raised before (e.g., Miller [2]) but we felt that earlier treatments had perhaps not reached a wide enough audience. The format for the debate consisted of contributions from invited panelists followed by an open discussion. The panelists were Chris Langton, Mark Bedau, Simon Kirby, and Inman Harvey—Hiroaki Kitano was scheduled to participate but regrettably could not attend the conference