Geography and History of Periodical Cicadas (Hemiptera: Cicadidae) in DuPage County, Illinois

The spatial distribution of periodical cicada (Magicicada septendecim L. and M. cassini Fisher) emergence in 2007 did not match either historical locations of woodlands or the cicadas’ own geography in the 19th and early 20th centuries in DuPage County, Illinois. Cicadas were present in forest areas that had remained above 61 ha throughout historic times, and they were absent from areas which at some point had been reduced below 52 ha by tree removal, mainly for agriculture. Isolation of forest areas also may have contributed to local extinctions. The insects have spread into new, urban woodlands created by residential plantings. Their distribution is associated with the early growth of towns along commuter railways in the eastern part of the county (toward Chicago). A peculiar gap in the main emergence area (encompassing two adjacent cities) may be the result of the cicadas shifting their emergence four years early. An active dispersal on 9–11 June, coinciding with the peak in cicada singing in forested areas, apparently placed scattered small groups of cicadas outside the main emergence area

Statistics of Pressure Fluctuations in Decaying, Isotropic Turbulence

We present results from a systematic direct-numerical simulation study of pressure fluctuations in an unforced, incompressible, homogeneous, and isotropic, three-dimensional turbulent fluid. At cascade completion, isosurfaces of low pressure are found to be organised as slender filaments, whereas the predominant isostructures appear sheet-like. We exhibit several new results, including plots of probability distributions of the spatial pressure-difference, the pressure-gradient norm, and the eigenvalues of the pressure-hessian tensor. Plots of the temporal evolution of the mean pressure-gradient norm, and the mean eigenvalues of the pressure-hessian tensor are also exhibited. We find the statistically preferred orientations between the eigenvectors of the pressure-hessian tensor, the pressure-gradient, the eigenvectors of the strain-rate tensor, the vorticity, and the velocity. Statistical properties of the non-local part of the pressure-hessian tensor are also exhibited, for the first time. We present numerical tests (in the viscous case) of some conjectures of Ohkitani [Phys. Fluids A {\bf 5}, 2570 (1993)] and Ohkitani and Kishiba [Phys. Fluids {\bf 7}, 411 (1995)] concerning the pressure-hessian and the strain-rate tensors, for the unforced, incompressible, three-dimensional Euler equations.Comment: 10 pages, 29 figures, Accepted for publication in Physical Review

A reconfigurable real-time morphological system for augmented vision

There is a significant number of visually impaired individuals who suffer sensitivity loss to high spatial frequencies, for whom current optical devices are limited in degree of visual aid and practical application. Digital image and video processing offers a variety of effective visual enhancement methods that can be utilised to obtain a practical augmented vision head-mounted display device. The high spatial frequencies of an image can be extracted by edge detection techniques and overlaid on top of the original image to improve visual perception among the visually impaired. Augmented visual aid devices require highly user-customisable algorithm designs for subjective configuration per task, where current digital image processing visual aids offer very little user-configurable options. This paper presents a highly user-reconfigurable morphological edge enhancement system on field-programmable gate array, where the morphological, internal and external edge gradients can be selected from the presented architecture with specified edge thickness and magnitude. In addition, the morphology architecture supports reconfigurable shape structuring elements and configurable morphological operations. The proposed morphology-based visual enhancement system introduces a high degree of user flexibility in addition to meeting real-time constraints capable of obtaining 93 fps for high-definition image resolution

Foreign Search and Seizure: The Fourth Amendment at Large

The Administration\u27s recent policy of Say No to Drugs has sparked a veritable war on drugs within our country. Outside our borders, on the high seas, and in foreign lands, the war on drugs has been fought to prevent their entry through our borders. This war is encroaching on the fourth amendment rights of persons suspected of drug trafficking who are subjected to search and seizure. This Comment examines the fourth amendment protection these people have received, and argues that the courts should uphold the fourth amendment, rather than pay it verbal service

COORDINATION DURING INITIAL ACQUISITION OF THREE-BALL JUGGLING

Bimanual coordination is critical for the performance of a number of continuous skills (e.g., walking, running, drumming, etc.). However, relatively little is known about how such coordination is developed and maintained. In the current study researchers sought to address this issue by examining coordination changes in bilateral elbow motion during initial acquisition of three-ball cascade juggling. Elbow motion was assessed using a set of both traditional (Average Amplitude; Avg. Amp) and more recently developed nonlinear time-series analyses (Approximate Entropy; ApEn – a measure of complexity within a single time series, and Average Mutual Information; AMI – the amount of information shared between two time-series) (Abarbanel, 1996; Pincus, 1995). It was hoped that together these analyses would lend new insights about bimanual coordination in continuous skills that could be used to develop more sophisticated biomechanical models of human movement and/or advance general motor theor