The status of Euaresta stelligera (Coquillett) (Diptera: Tephritidae)

Based on examination of morphological characters of specimens from throughout their ranges, Euaresta stelligera (Coquillett) is confirmed to be a distinct species from E. bellula (Snow). The diagnostic characters, distributions, and host plants of both species are discussed. New distribution records for E. aequalis (Loew) and E. tapetis (Coquillett) are also provided, and an error concerning the range of Valentibulla californica is noted

Independence-friendly cylindric set algebras

Independence-friendly logic is a conservative extension of first-order logic that has the same expressive power as existential second-order logic. In her Ph.D. thesis, Dechesne introduces a variant of independence-friendly logic called IFG logic. We attempt to algebraize IFG logic in the same way that Boolean algebra is the algebra of propositional logic and cylindric algebra is the algebra of first-order logic. We define independence-friendly cylindric set algebras and prove two main results. First, every independence-friendly cylindric set algebra over a structure has an underlying Kleene algebra. Moreover, the class of such underlying Kleene algebras generates the variety of all Kleene algebras. Hence the equational theory of the class of Kleene algebras that underly an independence-friendly cylindric set algebra is finitely axiomatizable. Second, every one-dimensional independence-friendly cylindric set algebra over a structure has an underlying monadic Kleene algebra. However, the class of such underlying monadic Kleene algebras does not generate the variety of all monadic Kleene algebras. Finally, we offer a conjecture about which subvariety of monadic Kleene algebras the class of such monadic Kleene algebras does generate.Comment: 42 pages. Submitted to the Logic Journal of the IGPL. See also http://math.colgate.edu/~amann

Optical Dipole Trapping beyond Rotating Wave Approximation: The case of Large Detuning

We show that the inclusion of counter-rotating terms, usually dropped in evaluations of interaction of an electric dipole of a two level atom with the electromagnetic field, leads to significant modifications of trapping potential in the case of large detuning. The results are shown to be in excellent numerical agreement with recent experimental findings, for the case of modes of Laguerre-Gauss spatial profile.Comment: 13 pages, 2 figure

Surface optical vortices

It is shown how the total internal reflection of orbital-angular-momentum-endowed light can lead to the generation of evanescent light possessing rotational properties in which the intensity distribution is firmly localized in the vicinity of the surface. The characteristics of these surface optical vortices depend on the form of the incident light and on the dielectric mismatch of the two media. The interference of surface optical vortices is shown to give rise to interesting phenomena, including pattern rotation akin to a surface optical Ferris wheel. Applications are envisaged to be in atom lithography, optical surface tweezers, and spanners

Critical issues in library management : organizing for leadership and decision-making

Papers from the thirty-fifth Allerton Institute. [October 24-26, 1993]Includes bibliographical references

Automated assembly of large space structures using an expert system executive

NASA LaRC has developed a unique testbed for investigating the practical problems associated with the assembly of large space structures using robotic manipulators. The testbed is an interdisciplinary effort which considers the full spectrum of assembly problems from the design of mechanisms to the development of software. This paper will describe the automated structures assembly testbed and its operation, detail the expert system executive and its development, and discuss the planned system evolution. Emphasis will be placed on the expert system development of the program executive. The executive program must be capable of directing and reliably performing complex assembly tasks with the flexibility to recover from realistic system errors. By employing an expert system, information pertaining to the operation of the system was encapsulated concisely within a knowledge base. This lead to a substantial reduction in code, increased flexibility, eased software upgrades, and realized a savings in software maintenance costs

A new species of Anastrepha from Amazonia : with redescriptions of A. caudata Stone and A. hendeliana Lima (Diptera: Tephritidae)

Three species of Anastrepha from upper Amazonia are described or redescribed and illustrated. They are considered closely related and are placed in the A. caudata species group. Anastrepha caudata Stone 1942 is redescribed based on the holotype, the only known specimen. Its type locality is probably São Paulo de Olivença in Amazonas, Brazil, not the state or city of São Paulo as previously assumed. Anastrepha hendeliana Lima 1934, new status, is removed from synonymy with A. longicauda Lima 1934 based on specimens from Brazil (Amazonas and Rondonia) and Colombia (Caquetá). The female is described for the first time. Anastrepha brunnealata, n. sp., is described from specimens from Venezuela (Amazonas) and probably Peru (Loreto). Anastrepha longicauda Lima is placed in the dentata species group.Se describen o redescriben e ilustran tres especies de Anastrepha del Amazonia. Ellas están consideradas cercanamente relacionadas y las ubican en el grupo de especies caudata. Se redescribe Anastrepha caudata Stone 1942 basado en el holotipo, el único especimen conocido. La localidad tipo probablemente es São Paulo de Olivença en el Amazonas, Brasil, no el estado o la ciudad de São Paulo como se asumió anteriormente. Se remueve Anastrepha hendeliana Lima 1934, stat. n., de la sinonómia de A. longicauda Lima 1934 basado en especimenes de Brasil (Amazonas y Rondonia) y Colombia (Caquetá). La hembra es descrita por primera vez. Se describe Anastrepha brunnealata, sp. n., de especimenes de Venezuela (Amazonas) y probablemente Peru (Loreto). Se ubica Anastrepha longicauda Lima en el grupo de especies dentata

Acoustic controlled rotation and orientation

Acoustic energy is applied to a pair of locations spaced about a chamber, to control rotation of an object levitated in the chamber. Two acoustic transducers applying energy of a single acoustic mode, one at each location, can (one or both) serve to levitate the object in three dimensions as well as control its rotation. Slow rotation is achieved by initially establishing a large phase difference and/or pressure ratio of the acoustic waves, which is sufficient to turn the object by more than 45 deg, which is immediately followed by reducing the phase difference and/or pressure ratio to maintain slow rotation. A small phase difference and/or pressure ratio enables control of the angular orientation of the object without rotating it. The sphericity of an object can be measured by its response to the acoustic energy