Chapter 9: Aquatic Macroinvertebrates, Section A: Aquatic Macroinvertebrates (Exclusive of Mosquitoes)

Final Report. Excerpt (Chapter 9, Section A) from The Des Plaines River Wetlands Demonstration Project, Volume II, Baseline Survey, edited by Donald L. Hey and Nancy S. PhilippiReport issued on: October 1985INHS Technical Report prepared for Wetlands Research, Inc

DID VIETNAM VETERANS GET SICKER IN THE 1990s? THE COMPLICATED EFFECTS OF MILITARY SERVICE ON SELF-REPORTED HEALTH

The veterans disability compensation (VDC) program, which provides a monthly stipend to disabled veterans, is the third largest American disability insurance program. Since the late 1990s, VDC growth has been driven primarily by an increase in claims from Vietnam veterans, raising concerns about costs as well as health. We use the draft lottery to study the long-term effects of Vietnam-era military service on health and work in the 2000 Census. These estimates show no significant overall effects on employment or work-related disability status, with a small effect on non-work-related disability for whites. On the other hand, estimates for white men with low earnings potential show a large negative impact on employment and a marked increase in non-work-related disability rates. The differential impact of Vietnam-era service on low-skill men cannot be explained by more combat or war-theatre exposure for the least educated, leaving the relative attractiveness of VDC for less skilled men and the work disincentives embedded in the VDC system as a likely explanation.

Did Vietnam Veterans Get Sicker in the 1990s? The Complicated Effects of Military Service on Self-Reported Health

The veterans disability compensation (VDC) program, which provides a monthly stipend to disabled veterans, is the third largest American disability insurance program. Since the late 1990s, VDC growth has been driven primarily by an increase in claims from Vietnam veterans, raising concerns about costs as well as health. We use the draft lottery to study the long-term effects of Vietnam-era military service on health and work in the 2000 Census. These estimates show no significant overall effects on employment or work-related disability status, with a small effect on non-work-related disability for whites. On the other hand, estimates for white men with low earnings potential show a large negative impact on employment and a marked increase in non-work-related disability rates. The differential impact of Vietnam-era service on low-skill men cannot be explained by more combat or wartheatre exposure for the least educated, leaving the relative attractiveness of VDC for less skilled men and the work disincentives embedded in the VDC system as a likely explanation.Public economics, social security and public pensions, health, education, welfare,labour, demographic economics

New Records of the Eastern Red Bat, Lasiurus borealis, from Cypress Hills Provincial Park, Saskatchewan: A Response to Climate Change?

During the summer of 2001 we captured two Eastern Red Bats (Lasiurus borealis) in Cypress Hills Provincial Park, Saskatchewan. A possible explanation for this range extension is a warming trend since 1965 documented for the area

Many-body Green's function theory for electron-phonon interactions: the Kadanoff-Baym approach to spectral properties of the Holstein dimer

We present a Kadanoff-Baym formalism to study time-dependent phenomena for systems of interacting electrons and phonons in the framework of many-body perturbation theory. The formalism takes correctly into account effects of the initial preparation of an equilibrium state, and allows for an explicit time-dependence of both the electronic and phononic degrees of freedom. The method is applied to investigate the charge neutral and non-neutral excitation spectra of a homogeneous, two-site, two-electron Holstein model. This is an extension of a previous study of the ground state properties in the Hartree (H), partially self-consistent Born (Gd) and fully self-consistent Born (GD) approximations published in Ref. [arXiv:1403.2968]. We show that choosing a homogeneous ground state solution leads to unstable dynamics for a sufficiently strong interaction, and that allowing a symmetry-broken state prevents this. The instability is caused by the bifurcation of the ground state and understood physically to be connected with the bipolaronic crossover of the exact system. This mean-field instability persists in the partially self-consistent Born approximation but is not found for the fully self-consistent Born approximation. By understanding the stability properties, we are able to study the linear response regime by calculating the density-density response function by time-propagation. This functions amounts to a solution of the Bethe-Salpeter equation with a sophisticated kernel. The results indicate that none of the approximations is able to describe the response function during or beyond the bipolaronic crossover for the parameters investigated. Overall, we provide an extensive discussion on when the approximations are valid, and how they fail to describe the studied exact properties of the chosen model system.Comment: 12 figure

Using New Selection Tools

The goal of most beef production systems is to increase or at least maintain profitability. Producers can attempt to increase profitability in a variety of ways that might include reducing feed costs, changing their marketing program, or perhaps by changing the performance of their herd through genetic improvement. Focusing on this latter option, there are two primary genetic tools available: selection and mating where selection refers to the selection of breeding animals and mating includes which females are mated to which bulls, for example, crossbreeding systems. This paper focuses on the former, the selection of the appropriate animals for a production system with the goal to improve profitability. The best tool available for making selection decisions is expected progeny differences (EPD). Over the years the number of EPD available to guide producers in making selection decisions has grown from 5 to over 15 in most cases. Simply put, the amount of information that the breeder must sift through to try to make a good selection decision has become overwhelming. The producer must determine which EPD have the greatest influence on their income and their expenses, and by how much—a daunting task. Historically this task has depended on the “intuition” and experience of the breeder. For instance, they know that selection for heavier weaning weight will increase the weight of calves sold at weaning, but that blind selection for weaning weight will also increase calving difficulty and if replacements are kept, likely increase cow size and feed costs. Breeders have been performing a balancing act with little concrete information on how important each of those traits is to their profitability. Fortunately, there are several tools that have recently become available to ease the process of combining the costs and the revenues of beef production with EPD to make selection decisions that will produce progeny which are more profitable

Fractal Descriptors in the Fourier Domain Applied to Color Texture Analysis

The present work proposes the development of a novel method to provide descriptors for colored texture images. The method consists in two steps. In the first, we apply a linear transform in the color space of the image aiming at highlighting spatial structuring relations among the color of pixels. In a second moment, we apply a multiscale approach to the calculus of fractal dimension based on Fourier transform. From this multiscale operation, we extract the descriptors used to discriminate the texture represented in digital images. The accuracy of the method is verified in the classification of two color texture datasets, by comparing the performance of the proposed technique to other classical and state-of-the-art methods for color texture analysis. The results showed an advantage of almost 3% of the proposed technique over the second best approach.Comment: Chaos, Volume 21, Issue 4, 201

Identifying and estimating the distributional effects of unionization and the long-term consequences of military service

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Economics, 2010.Cataloged from PDF version of thesis.Includes bibliographical references.This thesis is concerned with the economic consequences for individuals of two important U.S. labor market institutions: unionization and the military draft. The first chapter develops an econometric procedure for estimating quantile treatment effects in a regression discontinuity design. It shows nonparametric identification, develops estimators, including a data-driven bandwidth choice, and illustrates the methodology by estimating the effects of an Oklahoma universal pre-K program on the quantiles of student outcomes. The second chapter applies the econometric procedure developed in the first chapter and estimates effects of unionization on the distribution of employees' earnings using a regression discontinuity design based on union certification elections. The results suggest that unionization raises the lower end of the distribution by up to 25 log points, but has a large negative effect on the upper tail of earnings, with little effect on average earnings. Unionization also increases retention among workers with lower pre-election earnings, but decreases it for higher-earning workers. These effects are interpreted as reflecting the political incentives unions face in certification elections. The final chapter (joint with Joshua Angrist and Stacey Chen) explores the long-term effects of Vietnam-era military service on disability outcomes using a research design based on the draft lottery. We find no evidence that military service affected overall employment rates or overall work-limiting disability. At the same time, military service drastically increased federal transfer income, especially for lower skilled white men, among whom there was a large negative impact on employment and an increase in disability rates. The differential impact of Vietnam-era service on low-skilled men cannot be explained by more combat exposure for the least educated, leaving the relative attractiveness of VDC for less skilled men and the work disincentives embedded in the VDC system as a likely explanation.by Brigham R. Frandsen.Ph.D

Physico-chemical limnology and periphyton in a warm-water stream receiving wastewater treatment plant effluent

Physical, chemical, and biological parameters were monitored at five stations in the Asa Creek-Kaskaskia River system, Moultrie County, Illinois, from 12 September 1969 through 7 September 1970 to characterize these streams as a periphyton habitat. Periphyton accrual and periphytic bacterial uptake kinetics studies continued until 10 December 1970 to determine the effect of the effluent from the Sullivan wastewater treatment plant on assimilation of dissolved organic matter by the periphyton community. The results of the coordinated physical, chemical, and biological study of 34 parameters measured biweekly revealed that there was no gross evidence of any differences between the creek and river sampling sites as determined by these measurements. Wastewater treatment was of such high quality that the effluent was generally undetectable 2 km downstream from the outfall. Only nitrate- nitrogen, ammonia-nitrogen, and phosphorus (all forms) concentrations were directly attributable to the effluent in Asa Creek, the receiving stream. Of eight parameters measured during the periphyton accrual study, four were found to be significantly different among stations. These included standing crop (biomass), organic content, and productivities (biomass and caloric value). The range of production efficiency of the periphyton community was 0.004 to 0.165% among the five stations. Intrastation correlations among these parameters revealed that the discharge of effluent into Asa Creek coupled with Asa Creek's low stream order resulted in not only a wide flux of physical-chemical conditions, but had a varied effect on the periphyton. Greater stability in the Kaskaskia River, a higher order stream, was reflected in more predictable levels of physicochemical parameters and in more stable periphyton communities which developed there. Planktonic and pariphytic bacterial chemo-organotraphy, with acetate as the substrate, were measured and evaluated through enzyme kinetics analysis procedures. The maximum bacterial uptake velocity, the maximum natural substrate concentrations, and the substrate regeneration time of acetate, are presented. Bacterial uptake kinetics experiments demonstrated that the periphyton, at stations influenced by the wastewater treatment plant effluent, assimilated two to three times more dissolved organic matter than at stations not influenced by the effluent. The influence of the treatment plant was not as apparent for assimilation by planktonic bacteria. This reinforced the premise that the attached community was the most sensitive to subtle changes in the aquatic environment.U.S. Department of the InteriorU.S. Geological SurveyOpe

Fast Fourier Optimization: Sparsity Matters

Many interesting and fundamentally practical optimization problems, ranging from optics, to signal processing, to radar and acoustics, involve constraints on the Fourier transform of a function. It is well-known that the {\em fast Fourier transform} (fft) is a recursive algorithm that can dramatically improve the efficiency for computing the discrete Fourier transform. However, because it is recursive, it is difficult to embed into a linear optimization problem. In this paper, we explain the main idea behind the fast Fourier transform and show how to adapt it in such a manner as to make it encodable as constraints in an optimization problem. We demonstrate a real-world problem from the field of high-contrast imaging. On this problem, dramatic improvements are translated to an ability to solve problems with a much finer grid of discretized points. As we shall show, in general, the "fast Fourier" version of the optimization constraints produces a larger but sparser constraint matrix and therefore one can think of the fast Fourier transform as a method of sparsifying the constraints in an optimization problem, which is usually a good thing.Comment: 16 pages, 8 figure