Gyrokinetic Field Theory as a Gauge Transform or: gyrokinetic theory without Lie transforms

Gyrokinetic theory is a basis for treating magnetised plasma dynamics slower than particle gyrofrequencies where the scale of the background is larger than relevant gyroradii. The energy of field perturbations can be comparable to the thermal energy but smaller than the energy of the background magnetic field. Properly applied, it is a low-frequency gauge transform rather than a treatment of particle orbits, and more a representation in terms of gyrocenters rather than particles than an approximation. By making all transformations and approximations in the field/particle Lagrangian one preserves exact energetic consistency so that time symmetry ensures energy conservation and spatial axisymmetry ensures toroidal angular momentum conservation. This method draws on earlier experience with drift kinetic models while showing the independence of gyrokinetic representation from particularities of Lie transforms or specific ordering limits, and that the essentials of low-frequency magnetohydrodynamics, including the equilibrium, are recovered. It gives a useful basis for total-f electromagnetic gyrokinetic computation. Various versions of the representation based upon choice of parallel velocity space coordinate are illustrated.Comment: 33 pages, no figure

Dynamical Alignment in Three Species Tokamak Edge Turbulence

Three dimensional computations of self consistent three species gyrofluid turbulence are carried out for tokamak edge conditions. Profiles as well as disturbances in dependent variables are followed, running the dynamical system to transport equilibrium. The third species density shows a significant correlation with that of the electrons, regardless of initial conditions and drive mechanisms. For decaying systems the densities evolve toward each other. Companion tests with a simple two dimensional drift wave model show this persists even if the third species is a passively advected test field. Similarity in the transport character of electrons and the trace species does not imply that the electrons themselves have a test particle transport character.Comment: RevTeX 4, 21 pages, 15 figures, submitted to Physics of Plasma

A review of nonequilibrium effects and surface catalysis on shuttle heating

A review is given of the nonequilibrium calculation techniques by various authors over the past decade to predict heat fluxes to the windward side of the Space Shuttle orbiter. The results of these techniques are compared with measurements made on the first few flights of the Space Shuttle. The calculations attempt to account for finite rate chemistry in the shock layer around the vehicle and for finite rate catalytic atom recombination on the thermal protection materials. The techniques considered are the axisymmetric viscous shock layer method, three dimensional reacting Euler equation solutions coupled with axisymmetric analog boundary layer method, and a recently developed nonequilibrium 3-D viscous shock layer method

Eminent Domain after Kelo v. City of New London: Compensating for the Supreme Court’s Refusal to Enforce the Fifth Amendment

Governments, both state and federal, have the right to take private property for public use, provided that just compensation is paid. The Fifth Amendment to the United States Constitution sets the legal standard for these propositions; this power is known as the right of eminent domain. In the landmark decision, Kelo v. City of New London, the Supreme Court held that the taking of a citizen’s private property for economic development qualified as a public use within the meaning of the Fifth Amendment. Several scholars, legislatures, and individuals, have objected to Kelo’s extension of the power of eminent domain. The ruling has extended the government’s power of eminent domain to areas once thought unimaginable

Minimal surfaces in the Heisenberg group

We investigate the minimal surface problem in the three dimensional Heisenberg group, H, equipped with its standard Carnot-Caratheodory metric. Using a particular surface measure, we characterize minimal surfaces in terms of a sub-elliptic partial differential equation and prove an existence result for the Plateau problem in this setting. Further, we provide a link between our minimal surfaces and Riemannian constant mean curvature surfaces in H equipped with different Riemannian metrics approximating the Carnot-Caratheodory metric. We generate a large library of examples of minimal surfaces and use these to show that the solution to the Dirichlet problem need not be unique. Moreover, we show that the minimal surfaces we construct are in fact X-minimal surfaces in the sense of Garofalo and Nhieu.Comment: 26 pages, 12 figure

Observation of explosive collisionless reconnection in 3D nonlinear gyrofluid simulations

The nonlinear dynamics of collisionless reconnecting modes is investigated, in the framework of a three-dimensional gyrofluid model. This is the relevant regime of high-temperature plasmas, where reconnection is made possible by electron inertia and has higher growth rates than resistive reconnection. The presence of a strong guide field is assumed, in a background slab model, with Dirichlet boundary conditions in the direction of nonuniformity. Values of ion sound gyro-radius and electron collisionless skin depth much smaller than the current layer width are considered. Strong acceleration of growth is found at the onset to nonlinearity, while at all times the energy functional is well conserved. Nonlinear growth rates more than one order of magnitude higher than linear growth rates are observed when entering into the small-$\Delta'$ regime

Whoʼs Watching Us at Work? Toward a Structural-Perceptual Model of Electronic Monitoring and Surveillance in Organizations

Nearly 80% of organizations now employ some form of employee surveillance. This significant level of use infers a salient need for additional theory and research into the effects of monitoring and surveillance. Accordingly, this essay examines the panoptic effects of electronic monitoring and surveillance (EM/S) of social communication in the workplace and the underlying structural and perceptual elements that lead to these effects. It also provides future scholarly perspectives for studying EM/S and privacy in the organization from the vantage point of contemporary communication technologies, such as the telephone, voice mail, e-mail, and instant messaging, utilized for organizational communication. Finally, four propositions are presented in conjunction with a new communication-based model of EM/S, providing a framework incorporating three key components of the panoptic effect: (a) communication technology use, (b) organizational factors, and (c) organizational policies for EM/S

Veterans’ Benefits: Pension Benefit Programs

[Excerpt] The Department of Veterans Affairs (VA) administers pension programs for certain low-income veterans and their surviving spouses and dependent children. This report discusses the Improved Disability Pension, which makes payments to certain low-income veterans, and the Improved Death Pension, which makes payments to certain low-income surviving spouses and dependent children of deceased veterans. To qualify for either program, individuals must have become eligible for payments on or after January 1, 1979. Both pension programs were created by P.L. 95-588, the Veterans and Survivors Pension Improvement Act of 1978. In addition, this report discusses a special pension program for Medal of Honor recipients. This report does not discuss several other pension programs that are administered by the VA, such as the Old Law Disability Pension and the Section 306 Disability Pension, which make payments to low-income veterans, and the Old Law Death Pension and the Section 306 Death Pension, which make payments to low-income surviving spouses and dependent children of veterans; these programs apply only to veterans and their survivors who became entitled to such benefits before 1979. This report also does not discuss pension programs for veterans of specific periods of war before World War I, such as the Civil War, the Indian Wars, and the Spanish-American War. Finally, this report does not address the military retirement system. For information on that system, see CRS Report RL34751, Military Retirement: Background and Recent Developments, by Kristy N. Kamarck

SCF E3 Ligase Substrates Switch from CAN-D to Can-ubiquitylate

Liu et al. (2018) report a mathematical model predicting how the cellular repertoire of SCF E3 ligases is assembled by “adaptive exchange on demand,” with the limited pool of CUL1 scanning the vast sea of F-box proteins for those with substrates demanding ubiquitylation