Bright Line, Substantial Participation, or Something Else: Who is a Primary Violator Under Rule 10b-5?

This Note analyzes the competing theories currently used by courts and commentators to determine when a secondary actor’s conduct arises to the level of a primary violation under section 10(b) of the Securities and Exchange Act of 1934 and Securities and Exchange Commission rule 10b-5 on a theory of aiding and abetting primary violators. This Note proposes a workable and logical standard that can be used to differentiate a primary violation from mere aiding and abetting. Part I of the Note discusses the decision in Central Bank of Denver and the resulting dilemma that faced the lower courts in determining when a secondary actor is a primary violator. Part II provides an analytical discussion of the emergence of two tests often used to determine whether a secondary actor is a primary violator: the “bright line” and “substantial participation” tests. Finally, Part III discusses the elements of a primary violation of section 10(b) and rule 10b-5 as they relate to a secondary actor and proposes a workable and logical test to determine when a secondary actor’s conduct rises to the level of a primary violation

Time-dependent Schr\"odinger equations having isomorphic symmetry algebras. II. Symmetry algebras, coherent and squeezed states

Using the transformations from paper I, we show that the Schr\"odinger equations for: (1)systems described by quadratic Hamiltonians, (2) systems with time-varying mass, and (3) time-dependent oscillators, all have isomorphic Lie space-time symmetry algebras. The generators of the symmetry algebras are obtained explicitly for each case and sets of number-operator states are constructed. The algebras and the states are used to compute displacement-operator coherent and squeezed states. Some properties of the coherent and squeezed states are calculated. The classical motion of these states is deomonstrated.Comment: LaTeX, 22 pages, new format, edited, with added discussion of the classical motio

Economic Geography and the Fiscal Effects of Regional Integration,

In models of economic geography, plant-level scale economies and trade costs create incentives for spatial agglomeration of production into a manufacturing core and agricultural periphery, creating regional income differentials. We examine tax competition between national governments to influence the location of manufacturing activity. Labour is imperfectly mobile and governments impose redistributive taxes. Regional integration is modeled as either increased labour mobility or lower trade costs. We show that either type of integration may result in a decrease in the intensity of tax competition, and thus higher equilibrium taxes. Moreover, economic integration must increase taxes when the forces of agglomeration are the strongest.economic integration; economic geography; factor mobility; international trade; tax competition

Displacement-Operator Squeezed States. I. Time-Dependent Systems Having Isomorphic Symmetry Algebras

In this paper we use the Lie algebra of space-time symmetries to construct states which are solutions to the time-dependent Schr\"odinger equation for systems with potentials $V(x,\tau)=g^{(2)}(\tau)x^2+g^{(1)}(\tau)x +g^{(0)}(\tau)$. We describe a set of number-operator eigenstates states, $\{\Psi_n(x,\tau)\}$, that form a complete set of states but which, however, are usually not energy eigenstates. From the extremal state, $\Psi_0$, and a displacement squeeze operator derived using the Lie symmetries, we construct squeezed states and compute expectation values for position and momentum as a function of time, $\tau$. We prove a general expression for the uncertainty relation for position and momentum in terms of the squeezing parameters. Specific examples, all corresponding to choices of $V(x,\tau)$ and having isomorphic Lie algebras, will be dealt with in the following paper (II).Comment: 23 pages, LaTe

Intestinal macromolecular transport supporting adaptive immunity

The gastrointestinal tract performs opposing functions of nutrient absorption, barrier maintenance, and the delivery of luminal substances for the appropriate induction of tolerogenic or protective adaptive immunity. The single-layer epithelium lining the gastrointestinal tract is central to each of these functions by facilitating the uptake and processing of nutrients, providing a physical and chemical barrier to potential pathogens, and delivering macromolecular substances to the immune system to initiate adaptive immune responses. Specific transport mechanisms allow nutrient uptake and the delivery of macromolecules to the immune system while maintaining the epithelial barrier. This review examines historical observations supporting macromolecular transport by the intestinal epithelium, recent insights into the transport of luminal macromolecules to promote adaptive immunity, and how this process is regulated to promote appropriate immune responses. Understanding how luminal macromolecules are delivered to the immune system and how this is regulated may provide insight into the pathophysiology of inflammatory diseases of the gastrointestinal tract and potential preventative or therapeutic strategies. Keywords: Antigen Transport, Mucosal Tolerance, Goblet Cell