On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

Evolution of Pinnipedia lactation strategies: a potential role for α-lactalbumin?

Despite the considerable variation in milk composition found among mammals, a constituent common across all groups is lactose, the main sugar and osmole in most eutherians milk. Exceptions to this are the families Otariidae (fur seals and sea lions) and Odobenidae (walruses), where lactose has not been detected. We investigated the molecular basis for this by cloning α-lactalbumin, the modifier protein of the lactose synthase complex. A mutation was observed which, in addition to preventing lactose production, may enable otariids to maintain lactation despite the extremely long inter-suckling intervals during the mother's time at sea foraging (more than 23 days in some species)

REGULATION OF THE FREE-ADVERTISING AND THE FIRST AMENDMENT

The "new" line between communications that have full First Amendment protection and those that are subject to regulation is still in the process of being delineated by the Supreme Court; legal and mass a communication scholars are proposing a plethora of tests for future cases. Rather than proposing yet another test, this article starts from the premise that future advertising regulation cases will be based on legal philosophy and judicial "world view" as well as law and precedent. First Amendment law and advertising regulation concerns have historically been based on two different concerns and perspectives that have only recently been seen to interact. This article charts a perspective on the differences in the legal, philosophical and historical roots of these two areas, shows how and why they are now seen as interrelated and attempts to give some insight into possible future legal directions in this area. Copyright 1983 by The Policy Studies Organization.

THE AMBITIONS OF POLICY DESIGN

There is no shortage of warnings concerning the hazards of excessive ambition in consciously-pursued public policy. In the light of these cautions, this paper considers the appropriate ambitions for policy design. The critics have missed the target. There is no need to fear ambition in policy design, provided that openness in communications about policy is secured. Copyright 1988 by The Policy Studies Organization.

ON BECOMING MORE OF A POLICY SCIENTIST

This essay presents some subjective thoughts on becoming more of a policy scientist, based on nearly thirty years of intense interest in policymaking and its improvement. Written as a token of gratitude for the privilege of receiving the first Harold Lasswell Award from the Policy Studies Organization, the essay takes the form of advice to striving policy scientists in nine desiderata followed by five operational recommendations. Some readings for exploring the suggestions presented in this paper are included in the reference section. Copyright 1984 by The Policy Studies Organization.