Preliminary investigation of high power microwave plasmas for electrothermal thruster use

Results are reported from preliminary tests to evaluate the high power microwave electrothermal thruster (MET) concept, which employs a free-floating plasma discharge maintained by applied CW microwave power to heat a propellant gas flow. Stable plasmas have been created and maintained in helium (He), nitrogen (N2), and hydrogen (H2) as propellants in both the TM(sub 011) and TM(sub 012) modes at discharge pressures from 10 Pa to 69 kPa. Reproducible starting conditions of pressure and power have been documented for all the plasmas. Vortical inflow of the propellant gas was observed to cause the formation of on-axis 'spike' plasmas. The formation and unformation conditions of these plasmas were studied. Operation in the spike plasma condition enables maximum power absorption with minimum wall heating and offers maximum efficiency in heating the propellant gas. In the spike condition, plasmas of the three propellant gases were investigated in an open channel configuration to a maximum applied power level of 11.2 kW (in N2). Microwave power coupling efficiencies of over 90 percent were routinely obtained at absorbed power levels up to 2 kW. Magnetic nozzle effects were investigated with a superconducting solenoid Al magnet applying a high magnetic field to the plasmas in and exiting from the discharge tube

Earnings Losses of Displaced Workers

The 1990-1991 recession has intensified concerns about the consequences of workers' job losses. To estimate the magnitude and temporal pattern of displaced workers' earnings losses, we exploit an unusual administrative data set that includes both employees' quarterly earnings histories and information about their firms. We find that when high-tenure workers separate from distressed firms their long-term losses average 25 percent per year. Further, their losses mount even prior to separation, are not limited to workers in a few industrial sectors, and are substantial even for those who find new jobs in similar firms. This evidence suggests that displaced workers' earnings losses result largely from the loss of some unidentified attribute of the employment relationship.earnings, wages, losses, displaced, dislocated, workers, Jacobson, LaLonde, Sullivan

Long-term earnings losses of high-seniority displaced workers

Displaced workers

Can Pragmatism Be Radical? Richard Posner and Legal Pragmatism

Richard Posner\u27s Law, Pragmatism, and Democracy (2003) is the most comprehensive account to date of his pragmatic vision of the law and democracy. For the most part, Posner\u27s theory of pragmatism has been attacked externally, mainly by theorists unsympathetic to pragmatism. In contrast, in this Review, we contest Posner\u27s account of pragmatism from within the pragmatic tradition. We contend that Posner\u27s views are problematic not because they are pragmatic, but because they are often not pragmatic enough. We put Posner\u27s account of pragmatism to the pragmatic test by examining its implications. Posner views ideals as useless and philosophical theorizing as empty. Lacking any meaningful approach for scrutinizing social goals, however, pragmatism devolves into an efficiency exercise - finding the appropriate means to achieve our given ends. Posner\u27s account has little to say about the selection of ends. Accordingly, his attack on abstract ideals becomes, in effect, an endorsement of such ideals, since it leaves unreconstructed the dominant moral ideals of present society. In contrast, we return to the thought of the classical pragmatists (primarily John Dewey) to offer an alternative vision of pragmatism. This account better integrates theory and practice and provides more meaningful guidance about the choice of ends. Although Posner adopts many of the ideas of the classical pragmatists, he diverges in crucial ways that lead to internal inconsistencies with his own pragmatic commitments and to end up employing unpragmatic forms of reasoning. Posner finds himself in this position because the pragmatic ideas upon which he founds his theory have far more potent and revolutionary implications than Posner is willing to entertain. After setting forth his account of pragmatism, Posner attacks theories of deliberative democracy as unpragmatic. According to Posner, the pragmatist recognizes that it is too unrealistic and idealistic to expect most Americans to engage in meaningful political dialogue. Instead, Posner advances a concept of democracy based on the ideas of Joseph Schumpeter: Democracy should consist of a set of elite managers whose goal is to find the most efficient means to achieve our inherited ends. We argue that Posner\u27s account of democracy is not pragmatic at all - even on his own terms. Under Posner\u27s account, since people are not encouraged to make any effort to form a community on the basis of shared ideals, the dominant normative ideals of society are left to drift haphazardly. Posner views the equilibrium that emerges from individuals who pursue their own private interests as sufficient to generate the larger social ethos. We contend that this conclusion is deeply flawed. Additionally, we demonstrate that certain central features of deliberative democracy, far from being unpragmatic, are, in fact, deeply connected to pragmatic inquiry

Can Pragmatism Be Radical? Richard Posner and Legal Pragmatism

Richard Posner\u27s Law, Pragmatism, and Democracy (2003) is the most comprehensive account to date of his pragmatic vision of the law and democracy. For the most part, Posner\u27s theory of pragmatism has been attacked externally, mainly by theorists unsympathetic to pragmatism. In contrast, in this Review, we contest Posner\u27s account of pragmatism from within the pragmatic tradition. We contend that Posner\u27s views are problematic not because they are pragmatic, but because they are often not pragmatic enough. We put Posner\u27s account of pragmatism to the pragmatic test by examining its implications. Posner views ideals as useless and philosophical theorizing as empty. Lacking any meaningful approach for scrutinizing social goals, however, pragmatism devolves into an efficiency exercise - finding the appropriate means to achieve our given ends. Posner\u27s account has little to say about the selection of ends. Accordingly, his attack on abstract ideals becomes, in effect, an endorsement of such ideals, since it leaves unreconstructed the dominant moral ideals of present society. In contrast, we return to the thought of the classical pragmatists (primarily John Dewey) to offer an alternative vision of pragmatism. This account better integrates theory and practice and provides more meaningful guidance about the choice of ends. Although Posner adopts many of the ideas of the classical pragmatists, he diverges in crucial ways that lead to internal inconsistencies with his own pragmatic commitments and to end up employing unpragmatic forms of reasoning. Posner finds himself in this position because the pragmatic ideas upon which he founds his theory have far more potent and revolutionary implications than Posner is willing to entertain. After setting forth his account of pragmatism, Posner attacks theories of deliberative democracy as unpragmatic. According to Posner, the pragmatist recognizes that it is too unrealistic and idealistic to expect most Americans to engage in meaningful political dialogue. Instead, Posner advances a concept of democracy based on the ideas of Joseph Schumpeter: Democracy should consist of a set of elite managers whose goal is to find the most efficient means to achieve our inherited ends. We argue that Posner\u27s account of democracy is not pragmatic at all - even on his own terms. Under Posner\u27s account, since people are not encouraged to make any effort to form a community on the basis of shared ideals, the dominant normative ideals of society are left to drift haphazardly. Posner views the equilibrium that emerges from individuals who pursue their own private interests as sufficient to generate the larger social ethos. We contend that this conclusion is deeply flawed. Additionally, we demonstrate that certain central features of deliberative democracy, far from being unpragmatic, are, in fact, deeply connected to pragmatic inquiry

Doxycycline alters metabolism and proliferation of human cell lines.

The tetracycline antibiotics are widely used in biomedical research as mediators of inducible gene expression systems. Despite many known effects of tetracyclines on mammalian cells-including inhibition of the mitochondrial ribosome-there have been few reports on potential off-target effects at concentrations commonly used in inducible systems. Here, we report that in human cell lines, commonly used concentrations of doxycycline change gene expression patterns and concomitantly shift metabolism towards a more glycolytic phenotype, evidenced by increased lactate secretion and reduced oxygen consumption. We also show that these concentrations are sufficient to slow proliferation. These findings suggest that researchers using doxycycline in inducible expression systems should design appropriate controls to account for potential confounding effects of the drug on cellular metabolism

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http://archive.org/details/correlationstudy00sullNAN